JFS: call io_schedule() instead of schedule() to avoid deadlock

The introduction of Jens Axboe's explicit i/o plugging patches introduced a
deadlock in jfs.  This was caused by the process initiating I/O not
unplugging the queue before waiting on the commit thread.  The commit
thread itself was waiting for that I/O to complete.  Calling io_schedule()
rather than schedule() unplugs the I/O queue avoiding the deadlock, and it
appears to be the right function to call in any case.

Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index d558e51..6988a10 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -135,7 +135,7 @@
 	add_wait_queue(event, &wait);
 	set_current_state(TASK_UNINTERRUPTIBLE);
 	TXN_UNLOCK();
-	schedule();
+	io_schedule();
 	current->state = TASK_RUNNING;
 	remove_wait_queue(event, &wait);
 }