truncate: drop 'oldsize' truncate_pagecache() parameter

truncate_pagecache() doesn't care about old size since commit
cedabed49b39 ("vfs: Fix vmtruncate() regression").  Let's drop it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/bfs/file.c b/fs/bfs/file.c
index ad3ea14..ae28922 100644
--- a/fs/bfs/file.c
+++ b/fs/bfs/file.c
@@ -166,7 +166,7 @@
 	struct inode *inode = mapping->host;
 
 	if (to > inode->i_size)
-		truncate_pagecache(inode, to, inode->i_size);
+		truncate_pagecache(inode, inode->i_size);
 }
 
 static int bfs_write_begin(struct file *file, struct address_space *mapping,