Revert "configfs: fix a race in configfs_lookup()"

This reverts commit c709c7ca which is
commit c42dd069 upstream.

It causes pixel to not boot properly, so revert for now.

Change-Id: Iabbeae10643a6e81f6c99e04514c22b4ac91831e
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>