drm/nouveau/core: xtensa firmware size needs to be 0x40000 no matter what

The current logic is wrong since we send fw->size >> 8 to the
card. Rounding the size up by 0x100 and 0x1000 didn't seem to help,
the card still hung, so go back to what the blob does -- 0x40000.
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/engine/xtensa.c

@@ -118,7 +118,13 @@ _nouveau_xtensa_init(struct nouveau_object *object)
 			return ret;
 		}
 
-		ret = nouveau_gpuobj_new(object, NULL, fw->size, 0x1000, 0,
+		if (fw->size > 0x40000) {
+			nv_warn(xtensa, "firmware %s too large\n", name);
+			release_firmware(fw);
+			return -EINVAL;
+		}
+
+		ret = nouveau_gpuobj_new(object, NULL, 0x40000, 0x1000, 0,
 					 &xtensa->gpu_fw);
 		if (ret) {
 			release_firmware(fw);