Cleanup: correct unbalanced doxygen groups

Also add groups in some files.

source/blender/python/gpu/gpu_py.c

@@ -58,6 +58,7 @@ struct PyC_StringEnumItems bpygpu_dataformat_items[] = {
     {GPU_DATA_10_11_11_REV, "10_11_11_REV"},
     {0, NULL},
 };
+
 /** \} */
 
 /* -------------------------------------------------------------------- */

source/blender/python/gpu/gpu_py_select.c

@@ -56,6 +56,7 @@ static PyObject *pygpu_select_load_id(PyObject *UNUSED(self), PyObject *value)
   GPU_select_load_id(id);
   Py_RETURN_NONE;
 }
+
 /** \} */
 
 /* -------------------------------------------------------------------- */

source/blender/python/gpu/gpu_py_texture.c

@@ -527,6 +527,7 @@ PyTypeObject BPyGPUTexture_Type = {
 /* -------------------------------------------------------------------- */
 /** \name GPU Texture module
  * \{ */
+
 PyDoc_STRVAR(pygpu_texture_from_image_doc,
              ".. function:: from_image(image)\n"
              "\n"