sanitize vfs_fsync calling conventions

Now that the last user passing a NULL file pointer is gone we can remove
the redundant dentry argument and associated hacks inside vfs_fsynmc_range.

The next step will be removig the dentry argument from ->fsync, but given
the luck with the last round of method prototype changes I'd rather
defer this until after the main merge window.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index f084249..53e8bea 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1692,7 +1692,7 @@
 		 * and bypass the page cache, we must sync the file
 		 * first.
 		 */
-		vfs_fsync(file, file->f_dentry, 1);
+		vfs_fsync(file, 1);
 	}
 	/* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
 	if (!mddev->bitmap_info.external)