mesa: enable texture stencil8 for multisample
This fixes GL45-CTS.gtf44.GL31Tests.texture_stencil8.texture_stencil8_gl44 from the ogl conform suite. Reviewed-by:Ilia Mirkin <imirkin@alum.mit.edu> Cc: 10.6 11.0 <mesa-stable@lists.freedesktop.org> Signed-off-by:
Dave Airlie <airlied@redhat.com>