When setting RHSM into the container mode, we are creating symlinks
to /etc/rhsm and /etc/pki/entitlement directories. However, this
creates dangling symlinks if RHSM is not installed or user manually
removes one of these dirs.
If any of these directories is missing, skip other actions and
log the warning. Usually it means that RHSM is not actually used
or installed at all, so in these cases we can do the skip. The
only corner case when system could use RHSM without
/etc/pki/entitlement is when RHSM is configured to put these
certificate on a different path, and we do not support nor cover
such a scenario as we are not scanning the RHSM configuration at
all.
This also solves the problems on systems that does not have RHSM
available at all.