[MUTEX]: linux/mutex-debug.h needs linux/linkage.h

For FASTCALL() define.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/mutex-debug.h b/include/linux/mutex-debug.h
index 0ccd8f9..8138d9eb 100644
--- a/include/linux/mutex-debug.h
+++ b/include/linux/mutex-debug.h
@@ -1,6 +1,8 @@
 #ifndef __LINUX_MUTEX_DEBUG_H
 #define __LINUX_MUTEX_DEBUG_H
 
+#include <linux/linkage.h>
+
 /*
  * Mutexes - debugging helpers:
  */