venus: fix missing renderer destructions

With failed compatibility check, the created renderer must be destroyed
within vn_instance_init_renderer.

Cc: mesa-stable
Fixes: 25b8f4f714 ("venus: handle device probing properly.")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34613>
(cherry picked from commit 2a4675ee9fa2742da9826d1b5fb064b6a0066713)

.pick_status.json

@@ -434,7 +434,7 @@
         "description": "venus: fix missing renderer destructions",
         "nominated": true,
         "nomination_type": 2,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "25b8f4f7143f2e022df245ba2e1a2ab3ed4a2f90",
         "notes": null

src/virtio/vulkan/vn_instance.c

@@ -181,7 +181,7 @@ vn_instance_init_renderer(struct vn_instance *instance)
          vn_log(instance, "wire format version %d != %d",
                 renderer_info->wire_format_version, version);
       }
-      return VK_ERROR_INITIALIZATION_FAILED;
+      goto out_renderer_destroy;
    }
 
    version = vn_info_vk_xml_version();
@@ -197,7 +197,7 @@ vn_instance_init_renderer(struct vn_instance *instance)
                 VK_VERSION_MINOR(VN_MIN_RENDERER_VERSION),
                 VK_VERSION_PATCH(VN_MIN_RENDERER_VERSION));
       }
-      return VK_ERROR_INITIALIZATION_FAILED;
+      goto out_renderer_destroy;
    }
 
    uint32_t spec_version =
@@ -226,6 +226,12 @@ vn_instance_init_renderer(struct vn_instance *instance)
    }
 
    return VK_SUCCESS;
+
+out_renderer_destroy:
+   vn_renderer_destroy(instance->renderer, alloc);
+   /* needed by stub instance creation */
+   instance->renderer = NULL;
+   return VK_ERROR_INITIALIZATION_FAILED;
 }
 
 /* instance commands */
@@ -309,6 +315,7 @@ vn_CreateInstance(const VkInstanceCreateInfo *pCreateInfo,
 
    result = vn_instance_init_renderer(instance);
    if (result == VK_ERROR_INITIALIZATION_FAILED) {
+      assert(!instance->renderer);
       *pInstance = instance_handle;
       return VK_SUCCESS;
    }