vfs_acl_common: add an fsp extension when setting ACL

vfs_acl_common: add an fsp extension when setting ACL

This allows the module checking for the fsp extension variable setting_nt_acl
and will be used in the module functions for .sys_acl_set_fd_fn (so
sys_acl_set_fd_xattr() and sys_acl_set_fd_tdb()).

This depends on the previous code changes, so
won't be back ported. But for reference the
bug id is below.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14592

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>