libcap-ng: add host build

This patch adds the necessary host build infrastructure for libcap-ng.

While OpenWrt doesn't strictly need this right now, merging this change
prevents downstream projects (like prplOS) from having to fork the package
just to build their host tools, thus keeping the code bases closer.

Signed-off-by: Cedric CHEDALEUX <cedric.chedaleux@orange.com>

libs/libcap-ng/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libcap-ng
 PKG_VERSION:=0.8.4
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://people.redhat.com/sgrubb/libcap-ng
@@ -26,6 +26,7 @@ PKG_FIXUP:=autoreconf
 PKG_BUILD_FLAGS:=lto
 
 include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/host-build.mk
 
 define Package/libcap-ng/Default
   TITLE:=POSIX capabilities library
@@ -65,6 +66,15 @@ CONFIGURE_ARGS += \
     --without-python \
     --without-python3
 
+HOST_CONFIGURE_VARS += \
+    ac_cv_prog_swig_found=no
+
+HOST_CONFIGURE_ARGS += \
+    --without-python \
+    --without-python3
+
+HOST_PKG_BUILD_FLAGS:=lto
+
 define Build/InstallDev
 	$(INSTALL_DIR) $(1)/usr/include
 	$(CP) $(PKG_INSTALL_DIR)/usr/include/*.h $(1)/usr/include/
@@ -89,3 +99,4 @@ endef
 
 $(eval $(call BuildPackage,libcap-ng))
 $(eval $(call BuildPackage,libcap-ng-bin))
+$(eval $(call HostBuild))