init: Added /dev/null to fix rootfs issues.

When booting from rootfs, /dev/null generates attributes as 0 0, causing
service startup failure (ssh/nfs,...etc)

remove debug code: "echo abcd"

Signed-off-by: samin <samin.guo@starfivetech.com>

system/skeleton/init

@@ -19,7 +19,6 @@ for x in $(cat /proc/cmdline); do
 done
 
 if [ "x${ROOT}" = "x" ]; then
-	echo abcd
 	exec /sbin/init
 fi
 
@@ -27,8 +26,8 @@ mount -t sysfs sysfs /sys
 
 mdev -s
 
-mkdir /dev/pts
-mkdir /dev/shm
+mkdir -p /dev/pts
+mkdir -p /dev/shm
 mount -t devpts devpts /dev/pts
 mount -t tmpfs tmpfs /dev/shm
 mount -t tmpfs tmpfs /tmp
@@ -45,6 +44,9 @@ else
 	if [ ! -e /rootfs/dev/console ]; then
 		/bin/mknod /rootfs/dev/console c 5 1
 	fi
+	if [ ! -e /rootfs/dev/null ]; then
+		/bin/mknod /rootfs/dev/null c 1 3
+	fi
 fi
 
 mount -n -o move /proc /rootfs/proc