include: meson.mk: honor CONFIG_DEBUG

Set buildtype according to CONFIG_DEBUG.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
(cherry picked from commit be3e7a8)

Author: dangowrt

include/meson.mk

@@ -124,7 +124,7 @@ define Build/Configure/Meson
 	$(call Meson/CreateCrossFile,$(PKG_BUILD_DIR)/openwrt-cross.txt)
 	$(call Meson, \
 		setup \
-		--buildtype plain \
+		--buildtype $(if $(CONFIG_DEBUG),debug,plain) \
 		--native-file $(PKG_BUILD_DIR)/openwrt-native.txt \
 		--cross-file $(PKG_BUILD_DIR)/openwrt-cross.txt \
 		-Ddefault_library=both \