Fix install of nfs-ganesha-ceph for Debian/SuSE

Fix install of nfs-ganesha-ceph for Debian/SuSE

The Debian and SuSE installs for nfs-ganesha on the non-rhcs repository
requires you to allow_unauthenticated for Debian, and disable_gpg_check
for SuSE. The nfs-ganesha-rgw package already does this, but the
nfs-ganesha-ceph package will fail to install because of this same
issue.

This PR moves the installations to happen when the appropriate flags are
set to True (nfs_obj_gw & nfs_file_gw), but does it per distro (one for
SuSE and one for Debian) so that the appropriate flag can be passed to
ignore the GPG check.