staging: rtl8712: Remove duplicate #define for __attribute__ ((packed))

There is already a macro defined in linux/compiler.h.
Signed-off-by: Michael Fiedler <michael.fiedler@informatik.stud.uni-erlangen.de>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/rtl8712/osdep_service.h

@@ -236,7 +236,5 @@ static inline u32 _RND512(u32 sz)
 	return ((sz >> 9) + ((sz & 511) ? 1 : 0)) << 9;
 }
 
-#define STRUCT_PACKED __attribute__ ((packed))
-
 #endif