sssd_flush_cache() errors ignored

[alejandro-colomar]

shadow/lib/sssd.c

Line 41 in 40bb89b

return -1;

shadow/lib/sssd.h

Line 13 in 40bb89b

#define sssd_flush_cache(service) (0)

This function (actually the macro when it's not being compiled) triggered an error while enabling -Werror=all, due to (all) callers ignoring the return value. Do we need to care about that return value when this function fails?

Cc: @jhrozek