Do not prompt for username at login

Given you can login as root with no password on the console,
asking which user you would like to login as is rather pointless.

Do have to tweak /etc/issue though as busybox getty does not display it
without a prompt, and we want a whale.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

alpine/etc/issue

@@ -1,12 +1,12 @@
+
 Welcome to Moby
-Kernel \r on an \m (\l)
 
                         ##         .
                   ## ## ##        ==
                ## ## ## ## ##    ===
            /"""""""""""""""""\___/ ===
       ~~~ {~~ ~~~~ ~~~ ~~~~ ~~~ ~ /  ===- ~~~
-           \\______ o           __/
-             \\    \\         __/
-              \\____\\_______/
+           \______ o           __/
+             \    \         __/
+              \____\_______/
 

alpine/init

@@ -22,7 +22,8 @@ setup_console() {
 	# skip consoles already in inittab
 	grep -q "^$tty:" "$inittab" && return
 
-	echo "$tty::respawn:/sbin/getty $line $speed $tty $term" >> "$inittab"
+	echo "$tty::once:cat /etc/issue" >> "$inittab"
+	echo "$tty::respawn:/sbin/getty -n -l /bin/sh $line $speed $tty $term" >> "$inittab"
 	if ! grep -q -w "$tty" "$securetty"; then
 		echo "$tty" >> "$securetty"
 	fi