Merge LinuxKPI changes from DragonflyBSD:

- Map more Linux compiler related defines to FreeBSD ones.

Sponsored by:	Mellanox Technologies

sys/ofed/include/linux/compiler.h

@@ -2,7 +2,8 @@
  * Copyright (c) 2010 Isilon Systems, Inc.
  * Copyright (c) 2010 iX Systems, Inc.
  * Copyright (c) 2010 Panasas, Inc.
- * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
+ * Copyright (c) 2013-2015 Mellanox Technologies, Ltd.
+ * Copyright (c) 2015 François Tigeot
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -62,5 +63,12 @@
 #define typeof(x)			__typeof(x)
 
 #define	uninitialized_var(x)		x = x
+#define	__read_mostly __attribute__((__section__(".data.read_mostly")))
+#define	__always_unused			__unused
+#define	__must_check			__result_use_check
+
+#define	__printf(a,b)			__printflike(a,b)
+
+#define	barrier()			__asm__ __volatile__("": : :"memory")
 
 #endif	/* _LINUX_COMPILER_H_ */

sys/ofed/include/linux/types.h

@@ -36,8 +36,6 @@
 #include <linux/compiler.h>
 #include <asm/types.h>
 
-#define	__read_mostly __attribute__((__section__(".data.read_mostly")))
-
 #ifndef __bitwise__
 #ifdef __CHECKER__
 #define __bitwise__ __attribute__((bitwise))