mm: remove nopage

Nothing in the tree uses nopage any more.  Remove support for it in the
core mm code and documentation (and a few stray references to it in
comments).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/gfs2/ops_address.c

@@ -438,7 +438,7 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 	int error;
 
 	/*
-	 * Due to the order of unstuffing files and ->nopage(), we can be
+	 * Due to the order of unstuffing files and ->fault(), we can be
 	 * asked for a zero page in the case of a stuffed file being extended,
 	 * so we need to supply one here. It doesn't happen often.
 	 */