[PATCH] debug_locks.h: add "struct task_struct;"

Removes many, many "declared inside parameter list" warnings on parisc.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/debug_locks.h

 #ifndef __LINUX_DEBUG_LOCKING_H
 #define __LINUX_DEBUG_LOCKING_H
 
+struct task_struct;
+
 extern int debug_locks;
 extern int debug_locks_silent;