drm/nouveau: fix thinko in nv04_instmem.c

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nv04_instmem.c

@@ -30,7 +30,7 @@ nv04_instmem_determine_amount(struct drm_device *dev)
 		 * of vram.  For now, only reserve a small piece until we know
 		 * more about what each chipset requires.
 		 */
-		switch (dev_priv->chipset & 0xf0) {
+		switch (dev_priv->chipset) {
 		case 0x40:
 		case 0x47:
 		case 0x49: