Revert "ovl: relax permission checking on underlying layers"

Revert "ovl: relax permission checking on underlying layers"

This reverts commit 007ea44892e6fa963a0876a979e34890325c64eb.

The commit broke some selinux-testsuite cases, and it looks like there's no
straightforward fix keeping the direction of this patch, so revert for now.

The original patch was trying to fix the consistency of permission checks, and
not an observed bug.  So reverting should be safe.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>