UBUNTU: update list-udeb-updates for the linux-lts -> linux-hwe change

A long overdue update ...
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

debian/list-udeb-updates

@@ -24,7 +24,7 @@ if [ $# -ne 2 ]; then
 fi
 
 # Bail if the source package or version string isn't the format we expect
-if ! (expr match "$1" '^linux$' &>/dev/null || expr match "$1" '^linux-lts-[a-z]\+$' &>/dev/null)
+if ! (expr match "$1" '^linux$' &>/dev/null || expr match "$1" '^linux-hwe[a-z\-]*$' &>/dev/null)
 then
 	errecho "Invalid source package $1"
 	exit 1