[PATCH] fix remaining missing includes

Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch.  This should now allow not to include sched.h
from module.h, which is done by a followup patch.

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/wait.h b/include/linux/wait.h
index d38c9fe..d285182 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -54,6 +54,7 @@
 };
 typedef struct __wait_queue_head wait_queue_head_t;
 
+struct task_struct;
 
 /*
  * Macros for declaration and initialisaton of the datatypes