mesa: remove unused ctx->Driver.ActiveTexture() hook

src/mesa/drivers/common/driverfuncs.c

@@ -124,7 +124,6 @@ _mesa_init_driver_functions(struct dd_function_table *driver)
    driver->UnmapTexture = NULL;
    driver->TextureMemCpy = _mesa_memcpy; 
    driver->IsTextureResident = NULL;
-   driver->ActiveTexture = NULL;
    driver->UpdateTexturePalette = NULL;
 
    /* imaging */

src/mesa/drivers/dri/mach64/mach64_tex.c

@@ -565,7 +565,6 @@ void mach64InitTextureFuncs( struct dd_function_table *functions )
    functions->IsTextureResident		= driIsTextureResident;
 
    functions->UpdateTexturePalette	= NULL;
-   functions->ActiveTexture		= NULL;
 
    driInitTextureFormats();
 }

src/mesa/main/dd.h

@@ -537,11 +537,6 @@ struct dd_function_table {
    GLboolean (*IsTextureResident)( GLcontext *ctx,
                                    struct gl_texture_object *t );
 
-   /**
-    * Called by glActiveTextureARB() to set current texture unit.
-    */
-   void (*ActiveTexture)( GLcontext *ctx, GLuint texUnitNumber );
-
    /**
     * Called when the texture's color lookup table is changed.
     *