classes/meta: Add DISTRO_FEATURES check for gtk+/gtk3+

If you currently do a DISTRO_FEATURES_remove = "x11" with OE-Core, you
see failures due to dependency problems. The work in resolving this was
partially completed a while back. This adds in the markup mainly for
gtk/gtk3+ recipes and means "bitbake world" will work successfully.

Rather than code the gtk/gtk+ specific distro features into each recipe,
a shared variable is used.

(From OE-Core rev: ef967c70182eeccb59c7511d838a7ecb0b2315c1)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/python/python-pygtk_2.24.0.bb

@@ -26,7 +26,9 @@ S = "${WORKDIR}/${SRCNAME}-${PV}"
 
 EXTRA_OECONF = "--disable-docs --with-python-includes=${STAGING_INCDIR}/../"
 
-inherit autotools pkgconfig distutils-base
+inherit autotools pkgconfig distutils-base distro_features_check
+
+ANY_OF_DISTRO_FEATURES = "${GTK2DISTROFEATURES}"
 
 do_configure_prepend() {
 	install -m 0644 ${WORKDIR}/acinclude.m4 ${S}/