libjson-c: add host build (for libblobmsg-json)

Signed-off-by: Daniel Golle <[email protected]>

package/libs/libjson-c/Makefile

@@ -27,6 +27,7 @@ PKG_INSTALL:=1
 PKG_MAINTAINER:=Felix Fietkau <[email protected]>
 
 include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/host-build.mk
 
 TARGET_CFLAGS += $(FPIC) -Wno-implicit-fallthrough
 
@@ -56,3 +57,4 @@ define Package/libjson-c/install
 endef
 
 $(eval $(call BuildPackage,libjson-c))
+$(eval $(call HostBuild))