Don't depend on if_nametoindex from iphlpapi.dll.

This makes glib work on Windows XP again.

src/glib.mk

@@ -89,8 +89,7 @@ define $(PKG)_BUILD
         PKG_CONFIG='$(PREFIX)/bin/$(TARGET)-pkg-config' \
         GLIB_GENMARSHAL='$(PREFIX)/$(TARGET)/bin/glib-genmarshal' \
         GLIB_COMPILE_SCHEMAS='$(PREFIX)/$(TARGET)/bin/glib-compile-schemas' \
-        GLIB_COMPILE_RESOURCES='$(PREFIX)/$(TARGET)/bin/glib-compile-resources' \
-        $(if $(findstring w64-mingw32,$(TARGET)),  CFLAGS="-DHAVE_IF_NAMETOINDEX=1")
+        GLIB_COMPILE_RESOURCES='$(PREFIX)/$(TARGET)/bin/glib-compile-resources'
     $(MAKE) -C '$(1)/glib'    -j '$(JOBS)' install sbin_PROGRAMS= noinst_PROGRAMS=
     $(MAKE) -C '$(1)/gmodule' -j '$(JOBS)' install bin_PROGRAMS= sbin_PROGRAMS= noinst_PROGRAMS=
     $(MAKE) -C '$(1)/gthread' -j '$(JOBS)' install bin_PROGRAMS= sbin_PROGRAMS= noinst_PROGRAMS=