intel/blorp: Emit 3DSTATE_MULTISAMPLE directly

intel/blorp: Emit 3DSTATE_MULTISAMPLE directly

Previously, we relied on a driver hook for 3DSTATE_MULTISAMPLE.  However,
now that Vulkan and GL use the same sample positions, we can set up
3DSTATE_MULTISAMPLE directly in blorp and delete the driver hook.

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>