Rename __attribute__((packed)) --> __packed

Also unify __attribute__ ((..)) to __attribute__((..)) and
handle ((__packed__)) like ((packed))

Change-Id: Ie60a51c3fa92b5009724a5b7c2932e361bf3490c
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: https://review.coreboot.org/15921
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/northbridge/intel/haswell/haswell.h

@@ -186,13 +186,14 @@
 #define DMIDRCCFG	0xeb4	/* 32bit */
 
 #ifndef __ASSEMBLER__
+#include <compiler.h>
 static inline void barrier(void) { asm("" ::: "memory"); }
 
 struct ied_header {
 	char signature[10];
 	u32 size;
 	u8 reserved[34];
-} __attribute__ ((packed));
+} __packed;
 
 #define PCI_DEVICE_ID_HSW_MOBILE 0x0c04
 #define PCI_DEVICE_ID_HSW_ULT 0x0a04