Add initial support for arm64

Non-booting yet, copying and extending armhf for now.

debian/changelog

@@ -4,6 +4,8 @@ debian-cd (3.1.16) UNRELEASED; urgency=medium
   * Fix changelog date for 3.1.15. Closes: #751814
   * Fix up Gnome CD set installing xfce - logic in boot menu creation was
     broken. Closes: #756774
+  * Add trivial initial (non-booting) support for arm64, by copying and
+    extending armhf for now.
 
   [ Philipp Hahn ]
   * Fix word-splitting regexp in generate_di_list. Closes: #758512.

tools/boot/jessie/boot-arm

@@ -21,8 +21,13 @@ if [ "$DI_WWW_HOME" = "default" ];then
     # won't cope with that
     if [ "$ARCH" = armel ]; then
         DI_WWW_HOME="http://d-i.debian.org/daily-images/armel/daily"
-    else
+    elif [ "$ARCH" = armhf ]; then
         DI_WWW_HOME="http://d-i.debian.org/daily-images/armhf/daily"
+    elif [ "$ARCH" = arm64 ]; then
+        DI_WWW_HOME="http://d-i.debian.org/daily-images/arm64/daily"
+    else
+        echo "$0: unknown arch $ARCH; abort"
+	exit 1
     fi
     try_di_image_cache
 fi
@@ -32,5 +37,5 @@ cd $CDDIR/..
 add_mkisofs_opt $CDDIR/../$N.mkisofs_opts "-J -joliet-long"
 
 # Arm* is currently not bootable directly from CD in jessie, so bail out here
-echo "Armel/armhf booting disabled, check with Sledge"
+echo "$ARCH booting disabled for $CODENAME, check with Sledge"
 exit 0

tools/boot/jessie/boot-arm64

@@ -0,0 +1,2 @@
+#!/bin/bash
+. $BASEDIR/tools/boot/$DI_CODENAME/boot-arm

tools/generate_di+k_list

@@ -198,6 +198,13 @@ linux-image-mx5
 linux-image-omap
 #endif
 
+#ifdef ARCH_arm64
+initramfs-tools
+busybox
+flash-kernel
+linux-image-arm64
+#endif
+
 #ifdef ARCH_sparc
 initramfs-tools
 busybox