fuse: simplify request_wait()

wait_event_interruptible_exclusive_locked() will do everything
request_wait() does, so replace it.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>

diff --cc fs/fuse/dev.c
Simple merge