s3: VFS: shadow_copy2: In shadow_copy2_get_shadow_copy_data(), check for DIR_LIST...

s3: VFS: shadow_copy2: In shadow_copy2_get_shadow_copy_data(), check for DIR_LIST access once we already have a handle on the snap directory.

There's no sense in opening a synthetic pathref first in
order to check for DIR_LIST access, then open again to
do the SMB_VFS_NEXT_FDOPENDIR() for listing.

Just open once, and check for DIR_LIST access on the
open handle before calling SMB_VFS_NEXT_FDOPENDIR() for listing.

We no longer need check_access_snapdir(), which is
static, so comment it out. Removal next.

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