net: consolidate DHCP onto eth0 only

- rename DfW main interface eth0
- remove eth1 DHCP config
- create tap device in init script not interfaces file

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>

alpine/Dockerfile

@@ -20,6 +20,7 @@ RUN \
   rc-update add vsudd boot && \
   rc-update add sysklogd boot && \
   rc-update add hwclock boot && \
+  rc-update add tap-vsockd boot && \
   rc-update add networking boot && \
   rc-update add acpid default && \
   rc-update add chronyd default && \

alpine/etc/network/interfaces

@@ -4,10 +4,3 @@ iface lo inet loopback
 auto eth0
 iface eth0 inet dhcp
     udhcpc_opts -T 3 -A 3 -t 20 -O search
-
-auto eth1
-iface eth1 inet dhcp
-    udhcpc_opts -T 1 -A 3
-    metric 199
-    pre-up service tap-vsockd start
-    post-down service tap-vsockd stop

alpine/packages/tap-vsockd/etc/init.d/tap-vsockd

@@ -23,6 +23,7 @@ start()
 		--background \
 		--pidfile ${PIDFILE} \
 		-- \
+		--tap eth0 \
 		--pidfile "${PIDFILE}" \
 		--listen