Add `apt-get update` to ubuntu-cpc ppc64el builds so they use the new

sources.

debian/changelog

@@ -1,3 +1,10 @@
+livecd-rootfs (2.408.11) UNRELEASED; urgency=medium
+
+  * Add `apt-get update` to ubuntu-cpc ppc64el builds so they use the new
+    sources.
+
+ -- Daniel Watkins <daniel.watkins@canonical.com>  Fri, 07 Apr 2017 16:11:59 -0400
+
 livecd-rootfs (2.408.10) xenial; urgency=medium
 
   [ Adam Conrad ]

live-build/ubuntu-cpc/hooks/034-disk-image-ppc64el.binary

@@ -26,6 +26,7 @@ install_grub() {
     mkdir mountpoint
     mount_partition "${rootfs_dev_mapper}" mountpoint
 
+    chroot mountpoint apt-get -qqy update
     chroot mountpoint apt-get -qqy install grub2
     chroot mountpoint apt-get -qqy remove --purge grub-legacy-ec2