net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely)

Some code here depends on CONFIG_KMOD to not try to load
protocol modules or similar, replace by CONFIG_MODULES
where more than just request_module depends on CONFIG_KMOD
and and also use try_then_request_module in ebtables.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/can/af_can.c b/net/can/af_can.c
index 8035fbf5..7d4d2b3 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -128,8 +128,8 @@
 	if (net != &init_net)
 		return -EAFNOSUPPORT;
 
-#ifdef CONFIG_KMOD
-	/* try to load protocol module, when CONFIG_KMOD is defined */
+#ifdef CONFIG_MODULES
+	/* try to load protocol module kernel is modular */
 	if (!proto_tab[protocol]) {
 		err = request_module("can-proto-%d", protocol);