Ensure the proper hooks are copied for Ubuntu MATE (LP: #2058161).

live-build/auto/config

@@ -1522,7 +1522,7 @@ case $PROJECT:${SUBPROJECT:-} in
 	ubuntu-cpc:*|ubuntu-server:live|ubuntu:desktop-preinstalled| \
 		ubuntu-wsl:*|ubuntu-mini-iso:*|ubuntu:|ubuntu-oem:*| \
 		ubuntustudio-dvd:*|edubuntu:*|ubuntu-budgie:*|ubuntucinnamon:*|xubuntu:*| \
-	        ubuntukylin:*)
+	        ubuntukylin:*|ubuntu-mate:*)
 		# Ensure that most things e.g. includes.chroot are copied as is
 		for entry in /usr/share/livecd-rootfs/live-build/${PROJECT}/*; do
 			case $entry in