Update moby tool for onshutdown support

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

Makefile

@@ -20,7 +20,7 @@ endif
 
 PREFIX?=/usr/local/
 
-MOBY_COMMIT=4105b7ea313b04bfd930aa45b8a091e8e3a1b2ac
+MOBY_COMMIT=a261a33812ec2ba6650dc0b16353f537ade66355
 MOBY_VERSION=0.0
 bin/moby: tmp_moby_bin.tar | bin
 	tar xf $<

linuxkit.yml

@@ -14,6 +14,10 @@ onboot:
   - name: dhcpcd
     image: linuxkit/dhcpcd:4b7b8bb024cebb1bbb9c8026d44d7cbc8e202c41
     command: ["/sbin/dhcpcd", "--nobackground", "-f", "/dhcpcd.conf", "-1"]
+onshutdown:
+  - name: shutdown
+    image: busybox:latest
+    command: ["/bin/echo", "so long and thanks for all the fish"]
 services:
   - name: getty
     image: linuxkit/getty:deb9332e786e72591bd9be200bcc9c7a534eb754