UTIL: allow to skip default options for child processes
Currently the SSSD default options like e.g. --debug-level are added
unconditionally to the command line options of a child process when
started with the child helper functions.
If a binary from a different source should be started as a child by SSSD
those options might not be known or used differently. This patch adds an
option to exec_child_ex() which allows to skip the default options and
only add specific options.
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>