crocus: fix leak on gen4/5 stencil fallback blit path.

Noticed by Ilia.

Fixes: f3630548f1 ("crocus: initial gallium driver for Intel gfx 4-7")

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15100>

src/gallium/drivers/crocus/crocus_blit.c

@@ -433,6 +433,7 @@ crocus_blit(struct pipe_context *ctx, const struct pipe_blit_info *info)
                                              info->src.level,
                                              &info->src.box, NULL);
 
+               pipe_surface_release(ctx, &dst_view);
             }
             return;
          }