The atomic_read was accidentally replaced with atomic_inc_return,
which prevents the server from getting cleaned up and causes rmmod
to hang with a warning:

    Can't purge s=00000001

Fixes: 2757a4dc ("afs: Fix access after dec in put functions")
Signed-off-by: NMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20221130174053.2665818-1-marc.dionne@auristor.com/Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>