vfs_ceph{_new}: do not set errno upon successful call to libcephfs

vfs_ceph{_new}: do not set errno upon successful call to libcephfs

There is code in Samba that expects errno from a previous system call
to be preserved through a subsequent system call. Thus, avoid setting
"errno = 0" in status_code() and lstatus_code() upon successful return
from libcephfs API call.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15686

Signed-off-by: Shachar Sharon <ssharon@redhat.com>
Reviewed-by: Guenther Deschner <gd@samba.org>
Reviewed-by: Anoop C S <anoopcs@samba.org>