at86rf230: fix MAX_CSMA_RETRIES parameter

This patch fix a copy&paste failure for setting the MAX_CSMA_RETRIES
value of the at86rf212 chip which was introduced by commit
f2fdd67c6bc89de0100410efb37de69b1c98ac03 ("ieee802154: enable
smart transmitter features of RF212")

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Cc: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ieee802154/at86rf230.c

@@ -852,7 +852,7 @@ at86rf212_set_csma_params(struct ieee802154_dev *dev, u8 min_be, u8 max_be,
 	if (rc)
 		return rc;
 
-	return at86rf230_write_subreg(lp, SR_MAX_CSMA_RETRIES, max_be);
+	return at86rf230_write_subreg(lp, SR_MAX_CSMA_RETRIES, retries);
 }
 
 static int