Add support for multiple modifiers such as:

	int __one __two foo;

Also handle trailing known modifiers when defecting modifiers:

	int __one foo __read_mostly;
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>