initramfs-tools/hooks/reform: do nothing if running machine cannot be deduced

initramfs-tools/hooks/reform

@@ -23,11 +23,10 @@ case $MACHINE in
 		copy_file firmware /boot/ls1028a-mhdpfw.bin /lib/firmware
 		;;
 	"")
-		echo "unable to deduce target machine"
-		exit 1
+		echo "W: unable to deduce target machine for reform initramfs-hook" >&2
 		;;
 	*)
-		echo "unsupported machine: $MACHINE"
+		echo "E: unsupported machine: $MACHINE" >&2
 		exit 1;
 		;;
 esac