mesa: Use location VERT_ATTRIB_GENERIC0 for vertex attribute 0
In OpenGL 3.1 attribute 0 becomes non-magic, just like in OpenGL ES 2.0. Earlier versions of OpenGL used attribute 0 exclusively for vertex position. V2: Add a utility function _mesa_attr_zero_aliases_vertex() in varray.h Fixes 4 Khronos OpenGL CTS failures: glGetVertexAttrib depth24_basic depth24_precision rgb8_rgba8_rgb Cc: <mesa-stable@lists.freedesktop.org> Signed-off-by:Anuj Phogat <anuj.phogat@gmail.com> Reviewed-by:
Ian Romanick <ian.d.romanick@intel.com> (cherry picked from commit 49c71050)