Added ctx parameter to _mesa_debug()

Added _mesa_printf()
Updated SetDrawBuffer() function in all drivers (ala 4.0.3)
Import 4.0.3/DRI changes.

src/mesa/drivers/dos/dmesa.c

@@ -526,13 +526,11 @@ static void set_read_buffer (GLcontext *ctx, GLframebuffer *buffer,
 /*
  * Set the destination/draw buffer.
  */
-static GLboolean set_draw_buffer (GLcontext *ctx, GLenum mode)
+static void set_draw_buffer (GLcontext *ctx, GLenum mode)
 {
- if (mode==GL_BACK_LEFT) {
-    return GL_TRUE;
- } else {
-    return GL_FALSE;
- }
+   /*
+     XXX this has to be fixed
+   */
 }