s390/qeth: use true and false for boolean values

Return statements in functions returning bool should use true or false
instead of an integer value.

This issue was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/s390/net/qeth_l3_main.c

@@ -117,9 +117,9 @@ static bool qeth_l3_is_addr_covered_by_ipato(struct qeth_card *card,
 	int rc = 0;
 
 	if (!card->ipato.enabled)
-		return 0;
+		return false;
 	if (addr->type != QETH_IP_TYPE_NORMAL)
-		return 0;
+		return false;
 
 	qeth_l3_convert_addr_to_bits((u8 *) &addr->u, addr_bits,
 				  (addr->proto == QETH_PROT_IPV4)? 4:16);