[PATCH] gateway: Fix __connman_connection_gateway_add is_vpn6 calculation.

Address a regression introduced in commit 823d5a2a8cc4 ("connection:
Refactor '__connman_connection_gateway_add'.") in which the 'is_vpn6'
calculation was inadvertently copied-and-pasted from the 'is_vpn4'
calculation by correctly using the associated IPv6-related
'new_gateway' data members.

This stops WireGuard and other VPN-related plugins from faulting on
start-up.

Suggested-by: Gabriel Sanches <[email protected]>
Signed-off-by: Gabriel Sanches <[email protected]>
Tested-by: Christian Hewitt <[email protected]>
---
 src/gateway.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/gateway.c b/src/gateway.c
index 16c87f83b4d6..b2c211e2dc8d 100644
--- a/src/gateway.c
+++ b/src/gateway.c
@@ -3704,10 +3704,10 @@ int __connman_gateway_add(struct connman_service *service,
 					is_gateway_config_vpn(
 						new_gateway->ipv4_config);
 
-		is_vpn6 = do_ipv4 &&
-					new_gateway->ipv4_config &&
+		is_vpn6 = do_ipv6 &&
+					new_gateway->ipv6_config &&
 					is_gateway_config_vpn(
-						new_gateway->ipv4_config);
+						new_gateway->ipv6_config);
 
 	} else {
 		if (do_ipv4 && new_gateway->ipv4_config)
-- 
2.45.0