lantig: xway_legacy: mark subtarget as source-only

Due to RAM/ROM size limitations, this sub-target has been unable
to generate usable images for a long time. Mark them as source-only
to save some resource for the buildbot.

Signed-off-by: Shiji Yang <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/18745
Signed-off-by: Robert Marko <[email protected]>

target/linux/lantiq/xway_legacy/target.mk

@@ -1,7 +1,7 @@
 ARCH:=mips
 SUBTARGET:=xway_legacy
 BOARDNAME:=XWAY Legacy
-FEATURES+=atm ramdisk small_flash
+FEATURES+=atm ramdisk small_flash source-only
 CPU_TYPE:=24kc
 
 DEFAULT_PACKAGES+=kmod-leds-gpio kmod-gpio-button-hotplug swconfig