can: sja1000: use common prefix for all sja1000 defines

This is a follow up patch to:

    f901b6b can: sja1000: fix define conflict on SH

That patch fixed a define conflict between the SH architecture and the sja1000
driver, by addind a prefix to one macro only. This patch consistently renames
the prefix of the SJA1000 controller registers from "REG_" to "SJA1000_".

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/sja1000/kvaser_pci.c b/drivers/net/can/sja1000/kvaser_pci.c
index 37b0381..217585b 100644
--- a/drivers/net/can/sja1000/kvaser_pci.c
+++ b/drivers/net/can/sja1000/kvaser_pci.c
@@ -159,9 +159,9 @@
 	for (i = 0; i < MAX_NO_OF_CHANNELS; i++) {
 		/* reset chip */
 		iowrite8(MOD_RM, base_addr +
-			 (i * KVASER_PCI_PORT_BYTES) + REG_MOD);
+			 (i * KVASER_PCI_PORT_BYTES) + SJA1000_MOD);
 		status = ioread8(base_addr +
-				 (i * KVASER_PCI_PORT_BYTES) + REG_MOD);
+				 (i * KVASER_PCI_PORT_BYTES) + SJA1000_MOD);
 		/* check reset bit */
 		if (!(status & MOD_RM))
 			break;