mesa/bufferobj: make _mesa_delete_buffer_object externally accessible

gl_buffer_object has grown more complicated and requires cleanup. Using this
function from drivers will be more future-proof.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Cc: "11.0 11.1" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/mesa/main/bufferobj.c

@@ -447,7 +447,7 @@ _mesa_new_buffer_object(struct gl_context *ctx, GLuint name)
  *
  * Default callback for the \c dd_function_table::DeleteBuffer() hook.
  */
-static void
+void
 _mesa_delete_buffer_object(struct gl_context *ctx,
                            struct gl_buffer_object *bufObj)
 {

src/mesa/main/bufferobj.h

@@ -108,6 +108,10 @@ _mesa_initialize_buffer_object(struct gl_context *ctx,
                                struct gl_buffer_object *obj,
                                GLuint name);
 
+extern void
+_mesa_delete_buffer_object(struct gl_context *ctx,
+                           struct gl_buffer_object *bufObj);
+
 extern void
 _mesa_reference_buffer_object_(struct gl_context *ctx,
                                struct gl_buffer_object **ptr,