mediatek: mt7629: add missing CONFIG_LEDS_SMARTRG_LED

The config symbol has acceidentally been omitted when adding support for
Linux 6.18. Re-add it.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

Author: dangowrt

target/linux/mediatek/mt7629/config-6.18

@@ -171,6 +171,7 @@ CONFIG_IRQ_MSI_LIB=y
 CONFIG_IRQ_TIME_ACCOUNTING=y
 CONFIG_IRQ_WORK=y
 # CONFIG_LEDS_BRIGHTNESS_HW_CHANGED is not set
+# CONFIG_LEDS_SMARTRG_LED is not set
 CONFIG_LIBFDT=y
 CONFIG_LOCK_DEBUGGING_SUPPORT=y
 CONFIG_LOCK_SPIN_ON_OWNER=y