fs: dlm: fix cleanup pending ops when interrupted

Immediately clean up a posix lock request if it is interrupted
while waiting for a result from user space (dlm_controld.)  This
largely reverts the recent commit b92a4e3f ("fs: dlm: change
posix lock sigint handling"). That previous commit attempted
to defer lock cleanup to the point in time when a result from
user space arrived. The deferred approach was not reliable
because some dlm plock ops may not receive replies.

Cc: stable@vger.kernel.org
Fixes: b92a4e3f ("fs: dlm: change posix lock sigint handling")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>