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/cpu/x86/smm/smihandler.c

@@ -28,7 +28,7 @@ static int do_driver_init = 1;
 typedef enum { SMI_LOCKED, SMI_UNLOCKED } smi_semaphore;
 
 /* SMI multiprocessing semaphore */
-static __attribute__ ((aligned(4))) volatile smi_semaphore smi_handler_status
+static __attribute__((aligned(4))) volatile smi_semaphore smi_handler_status
 	= SMI_UNLOCKED;
 
 static int smi_obtain_lock(void)