SYSDB: Remove code causing a covscan warning
    
    There's no reason to check for both ret != EOK and sanitized == NULL, as
    the second should never ever happen.
    
    This check is causing a clang warning in our code:
    
     Defect type: CLANG_WARNING
     1. sssd-1.16.0/src/db/sysdb_ops.c:4223:9: warning: Dereference of undefined pointer value
     #     if (res->count > 1) {
     #         ^~~~~~~~~~
     4. sssd-1.16.0/src/db/sysdb_ops.c:4199:5: note: 'res' declared without an initial value
     #     struct ldb_result *res;
     #     ^~~~~~~~~~~~~~~~~~~~~~
     7. sssd-1.16.0/src/db/sysdb_ops.c:4202:9: note: Assuming 'sid_str' is non-null
     #     if (!sid_str) return EINVAL;
     #         ^~~~~~~~
     10. sssd-1.16.0/src/db/sysdb_ops.c:4202:5: note: Taking false branch
     #     if (!sid_str) return EINVAL;
     #     ^
     13. sssd-1.16.0/src/db/sysdb_ops.c:4205:9: note: Assuming 'tmp_ctx' is non-null
     #     if (!tmp_ctx) {
     #         ^~~~~~~~
     16. sssd-1.16.0/src/db/sysdb_ops.c:4205:5: note: Taking false branch
     #     if (!tmp_ctx) {
     #     ^
     19. sssd-1.16.0/src/db/sysdb_ops.c:4209:11: note: Calling 'sysdb_search_object_by_sid'
     #     ret = sysdb_search_object_by_sid(tmp_ctx, domain, sid_str, NULL, &res;;
     #           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     22. sssd-1.16.0/src/db/sysdb_ops.c:4960:12: note: Calling 'sysdb_search_object_by_str_attr'
     #     return sysdb_search_object_by_str_attr(mem_ctx, domain, SYSDB_SID_FILTER,
     #            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     25. sssd-1.16.0/src/db/sysdb_ops.c:4872:5: note: Taking false branch
     #     if (str == NULL) {
     #     ^
     28. sssd-1.16.0/src/db/sysdb_ops.c:4877:9: note: Assuming 'ret' is equal to 0
     #     if (ret != EOK || sanitized == NULL) {
     #         ^~~~~~~~~~
     31. sssd-1.16.0/src/db/sysdb_ops.c:4877:9: note: Left side of '||' is false
     32. sssd-1.16.0/src/db/sysdb_ops.c:4877:23: note: Assuming 'sanitized' is equal to null
     #     if (ret != EOK || sanitized == NULL) {
     #                       ^~~~~~~~~~~~~~~~~
     35. sssd-1.16.0/src/db/sysdb_ops.c:4877:5: note: Taking true branch
     #     if (ret != EOK || sanitized == NULL) {
     #     ^
     38. sssd-1.16.0/src/db/sysdb_ops.c:4878:9: note: Left side of '||' is false
     #         DEBUG(SSSDBG_OP_FAILURE, "sss_filter_sanitize failed.\n");
     #         ^
     41. sssd-1.16.0/src/util/debug.h:123:9: note: expanded from macro 'DEBUG'
     #     if (DEBUG_IS_SET(__debug_macro_level)) { \
     #         ^
     44. sssd-1.16.0/src/util/debug.h:135:30: note: expanded from macro 'DEBUG_IS_SET'
     # #define DEBUG_IS_SET(level) (debug_level & (level) || \
     #                              ^
     47. sssd-1.16.0/src/db/sysdb_ops.c:4878:9: note: Assuming 'debug_level' is not equal to 0
     #         DEBUG(SSSDBG_OP_FAILURE, "sss_filter_sanitize failed.\n");
     #         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     50. sssd-1.16.0/src/util/debug.h:123:9: note: expanded from macro 'DEBUG'
     #     if (DEBUG_IS_SET(__debug_macro_level)) { \
     #         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     53. sssd-1.16.0/src/util/debug.h:136:30: note: expanded from macro 'DEBUG_IS_SET'
     #                             (debug_level == SSSDBG_UNRESOLVED && \
     #                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     56. sssd-1.16.0/src/db/sysdb_ops.c:4878:9: note: Left side of '&&' is false
     57. sssd-1.16.0/src/util/debug.h:123:9: note: expanded from macro 'DEBUG'
     #     if (DEBUG_IS_SET(__debug_macro_level)) { \
     #         ^
     60. sssd-1.16.0/src/util/debug.h:136:63: note: expanded from macro 'DEBUG_IS_SET'
     #                             (debug_level == SSSDBG_UNRESOLVED && \
     #                                                               ^
     63. sssd-1.16.0/src/db/sysdb_ops.c:4878:9: note: Loop condition is false. Exiting loop
     64. sssd-1.16.0/src/util/debug.h:121:35: note: expanded from macro 'DEBUG'
     # #define DEBUG(level, format, ...) do { \
     #                                   ^
     67. sssd-1.16.0/src/db/sysdb_ops.c:4879:9: note: Control jumps to line 4892
     #         goto done;
     #         ^
     70. sssd-1.16.0/src/db/sysdb_ops.c:4960:12: note: Returning from 'sysdb_search_object_by_str_attr'
     #     return sysdb_search_object_by_str_attr(mem_ctx, domain, SYSDB_SID_FILTER,
     #            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     73. sssd-1.16.0/src/db/sysdb_ops.c:4209:11: note: Returning from 'sysdb_search_object_by_sid'
     #     ret = sysdb_search_object_by_sid(tmp_ctx, domain, sid_str, NULL, &res;;
     #           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     76. sssd-1.16.0/src/db/sysdb_ops.c:4211:5: note: Taking false branch
     #     if (ret == ENOENT) {
     #     ^
     79. sssd-1.16.0/src/db/sysdb_ops.c:4217:12: note: Taking false branch
     #     } else if (ret != EOK) {
     #            ^
     82. sssd-1.16.0/src/db/sysdb_ops.c:4223:9: note: Dereference of undefined pointer value
     #     if (res->count > 1) {
     #         ^~~~~~~~~~
     #  4221|       }
     #  4222|
     #  4223|->     if (res->count > 1) {
     #  4224|           DEBUG(SSSDBG_FATAL_FAILURE, "getbysid call returned more than one " \
     #  4225|                                        "result !?!\n");
    
    Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
    
    Reviewed-by: Pavel Březina <pbrezina@redhat.com>