[PATCH] linux/timer.h needs linux/stddef.h

From: Christoph Hellwig <hch@lst.de>

timer.h is using NULL and thus needs stddef.h, without it some drivers
break on alpha.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/timer.h

@@ -4,6 +4,7 @@
 #include <linux/config.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
+#include <linux/stddef.h>
 
 struct tvec_t_base_s;