SYSDB: Rework sysdb_cache_connect()
As sysdb_cache_connect() has two very specific use cases (connect to the
cache and connect to the timestamp cache) and each of those calls have a
predetermined/fixed sets of values for a few parameters, let's try to
make the code a bit simpler to follow by having explicit functions for
connecting to the cache and connecting to the timestamp cache.
Macros could be used as well, but I have a slightly preference for
having two new functions instead of macros accessing internal parameters
of the macro's parameter.
Signed-off-by: Fabiano Fidêncio <firstname.lastname@example.org>
Reviewed-by: Jakub Hrozek <email@example.com>