vrend: restore GL_FRAMEBUFFER after clobbering

Both of these functions clobber the framebuffer-binding on
general-purpose GL contexts, which is bad for performance.

Tested-by: Jakob Bornecrantz <jakob@collabora.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Signed-off-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Signed-off-by: Jakob Bornecrantz <jakob@collabora.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

src/vrend_renderer.c

@@ -7275,7 +7275,7 @@ void vrend_renderer_resource_copy_region(struct vrend_context *ctx,
                      dstx + src_box->width,
                      dy2,
                      glmask, GL_NEAREST);
-
+   glBindFramebuffer(GL_FRAMEBUFFER, ctx->sub->fb_id);
 }
 
 static void vrend_renderer_blit_int(struct vrend_context *ctx,
@@ -7482,6 +7482,7 @@ static void vrend_renderer_blit_int(struct vrend_context *ctx,
                         dst_y2,
                         glmask, filter);
    }
+   glBindFramebuffer(GL_FRAMEBUFFER, ctx->sub->fb_id);
 
    if (make_intermediate_copy) {
       vrend_renderer_resource_destroy(intermediate_copy, false);