shorten loops over color bufs

src/mesa/pipe/softpipe/sp_clear.c

@@ -59,7 +59,7 @@ softpipe_clear(struct pipe_context *pipe, struct pipe_surface *ps,
       return;
    }
 
-   for (i = 0; i < PIPE_MAX_COLOR_BUFS; i++) {
+   for (i = 0; i < softpipe->framebuffer.num_cbufs; i++) {
       if (ps == sp_tile_cache_get_surface(softpipe->cbuf_cache[i])) {
          sp_tile_cache_clear(softpipe->cbuf_cache[i], clearValue);
          return;

src/mesa/pipe/softpipe/sp_context.c

@@ -94,7 +94,7 @@ softpipe_unmap_surfaces(struct softpipe_context *sp)
    struct pipe_surface *ps;
    uint i;
 
-   for (i = 0; i < PIPE_MAX_COLOR_BUFS; i++)
+   for (i = 0; i < sp->framebuffer.num_cbufs; i++)
       sp_flush_tile_cache(sp, sp->cbuf_cache[i]);
    sp_flush_tile_cache(sp, sp->zbuf_cache);
    sp_flush_tile_cache(sp, sp->sbuf_cache);

src/mesa/pipe/softpipe/sp_flush.c

@@ -55,7 +55,7 @@ softpipe_flush( struct pipe_context *pipe,
     * - flush the render cache
     */
 
-   for (i = 0; i < PIPE_MAX_COLOR_BUFS; i++)
+   for (i = 0; i < softpipe->framebuffer.num_cbufs; i++)
       if (softpipe->cbuf_cache[i])
          sp_flush_tile_cache(softpipe, softpipe->cbuf_cache[i]);