Exported the software renderer texture functions to make easier to create

a renderer based on a framebuffer.

Fixed an initialization bug with the dummy video display mode.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402589

src/video/SDL_renderer_sw.h

@@ -25,4 +25,7 @@
 
 extern SDL_RenderDriver SW_RenderDriver;
 
+/* Set up SDL_Surface texture functions for a renderer */
+void Setup_SoftwareRenderer(SDL_Renderer * renderer);
+
 /* vi: set ts=4 sw=4 expandtab: */