ocfs2: remove handle argument to ocfs2_start_trans()

All callers either pass in NULL directly, or a local variable that is
already set to NULL.

The internals of ocfs2_start_trans() get a nice cleanup as a result.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index e927758..7527358 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -67,7 +67,7 @@
 	if (!S_ISDIR(inode->i_mode))
 		flags &= ~OCFS2_DIRSYNC_FL;
 
-	handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
+	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
 	if (IS_ERR(handle)) {
 		status = PTR_ERR(handle);
 		mlog_errno(status);