lavapipe: use null probe path on win32

Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7208>

src/gallium/frontends/lavapipe/lvp_device.c

@@ -180,6 +180,7 @@ VKAPI_ATTR void VKAPI_CALL lvp_DestroyInstance(
    vk_free(&instance->vk.alloc, instance);
 }
 
+#ifndef _WIN32
 static void lvp_get_image(struct dri_drawable *dri_drawable,
                           int x, int y, unsigned width, unsigned height, unsigned stride,
                           void *data)
@@ -205,6 +206,7 @@ static struct drisw_loader_funcs lvp_sw_lf = {
    .put_image = lvp_put_image,
    .put_image2 = lvp_put_image2,
 };
+#endif
 
 static VkResult
 lvp_enumerate_physical_devices(struct lvp_instance *instance)
@@ -219,7 +221,11 @@ lvp_enumerate_physical_devices(struct lvp_instance *instance)
 
    assert(instance->num_devices == 1);
 
+#ifdef _WIN32
+   pipe_loader_sw_probe_null(&instance->devs);
+#else
    pipe_loader_sw_probe_dri(&instance->devs, &lvp_sw_lf);
+#endif
 
    result = lvp_physical_device_init(&instance->physicalDevice,
                                      instance, &instance->devs[0]);