drm/nvc0: add initial memory type detection

Uses only the VBIOS tables, from what I can tell this is what NVIDIA do
too, I was able to change the detected memory type by modifying this table
on a NVC1 chipset.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvc0_vram.c

@@ -115,6 +115,8 @@ nvc0_vram_init(struct drm_device *dev)
 	NV_DEBUG(dev, "0x100800: 0x%08x\n", nv_rd32(dev, 0x100800));
 	NV_DEBUG(dev, "parts 0x%08x bcast_mem_amount 0x%08x\n", parts, bsize);
 
+	dev_priv->vram_type = nouveau_mem_vbios_type(dev);
+
 	/* read amount of vram attached to each memory controller */
 	part = 0;
 	while (parts) {