[PATCH] kill open-coded offsetof in cm4000_cs.c ZERO_DEV()

... to make sure that it doesn't break again when a field changes (see
"[PATCH] pcmcia: fix zeroing of cm4000_cs.c data" for recent example).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

drivers/char/pcmcia/cm4000_cs.c

@@ -149,12 +149,7 @@ struct cm4000_dev {
 #define	ZERO_DEV(dev)  						\
 	memset(&dev->atr_csum,0,				\
 		sizeof(struct cm4000_dev) - 			\
-		/*link*/ sizeof(struct pcmcia_device *) - 	\
-		/*node*/ sizeof(dev_node_t) - 			\
-		/*atr*/ MAX_ATR*sizeof(char) - 			\
-		/*rbuf*/ 512*sizeof(char) - 			\
-		/*sbuf*/ 512*sizeof(char) - 			\
-		/*queue*/ 4*sizeof(wait_queue_head_t))
+		offsetof(struct cm4000_dev, atr_csum))
 
 static struct pcmcia_device *dev_table[CM4000_MAX_DEV];
 static struct class *cmm_class;