[PATCH] knfsd: simplify nlmsvc_invalidate_all

As a result of previous patches, the loop in nlmsvc_invalidate_all just sets
h_expires for all client/hosts to 0 (though does it in a very complicated
way).

This was possibly meant to trigger early garbage collection but half the time
'0' is in the future and so it infact delays garbage collection.

Pre-aging the 'hosts' is not really needed at this point anyway so we throw
out the loop and nlm_find_client which is no longer needed.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>