UPSTREAM: Revert "proc: don't allow async path resolution of /proc/self components"

[ Upstream commit 9e8d9e82 ]

This reverts commit 8d4c3e76.

No longer needed, as the io-wq worker threads have the right identity.

Change-Id: I6c12f6f957e1c789f4fd5b21379d167f17feb3ea
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit b76c5373)
Bug: 268174392
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>