virglrenderer depends on 2 packages:
* mesa: requires one of distro features opengl or vulkan
* libepoxy: requires distro feature opengl
So make virglrenderer requires distro feature opengl. Otherwise it fails
to build world if 'opengl' doesn't exist in DISTRO_FEATURES.
(From OE-Core rev: 63c98d10231271135013e04749ac351247bd6546)
Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>