gallium: fix shader mem leak

src/mesa/state_tracker/st_cb_bitmap.c

@@ -198,6 +198,10 @@ combined_bitmap_fragment_program(GLcontext *ctx)
          _mesa_combine_programs(ctx,
                                 &bitmap_prog->Base.Base, &stfp->Base.Base);
       stfp->bitmap_program->bitmap_sampler = sampler;
+
+      /* done with this after combining */
+      st_reference_fragprog(st, &bitmap_prog, NULL);
+
 #if 0
       {
          struct gl_program *p = &stfp->bitmap_program->Base.Base;