mesa/st: enable ARB_fragment_layer_viewport

If multiple viewports are supported, that implies the presence of a GS
and layered rendering, so we can enable ARB_fragment_layer_viewport as
well.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>
3 files changed