glsl: check total count of multi-slot double vertex attribs
The spec is vague all over the place about this, but this seems to be the intent, we can probably make this optional later if someone makes hw that cares and writes a driver. Basically we need to double count some of the d types but only for totalling not for slot number assignment. Reviewed-by:Ilia Mirkin <imirkin@alum.mit.edu> Signed-off-by:
Dave Airlie <airlied@redhat.com>