futex: Change 3rd arg of fetch_robust_entry() to unsigned int*

Sparse complains:
 kernel/futex.c:2495:59: warning: incorrect type in argument 3 (different signedness)

Make 3rd argument of fetch_robust_entry() 'unsigned int'.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Darren Hart <dvhltc@us.ibm.com>
LKML-Reference: <1284468228-8723-1-git-send-email-namhyung@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index d49afb2..06da4df 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -19,7 +19,7 @@
  */
 static inline int
 fetch_robust_entry(compat_uptr_t *uentry, struct robust_list __user **entry,
-		   compat_uptr_t __user *head, int *pi)
+		   compat_uptr_t __user *head, unsigned int *pi)
 {
 	if (get_user(*uentry, head))
 		return -EFAULT;