radeonsi: properly destroy the GS copy shader and scratch_bo for compute

Cc: 10.2 10.3 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 7261885..9d2cc80 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -2973,5 +2973,9 @@
 
 void si_shader_destroy(struct pipe_context *ctx, struct si_shader *shader)
 {
+	if (shader->gs_copy_shader)
+		si_shader_destroy(ctx, shader->gs_copy_shader);
+
 	r600_resource_reference(&shader->bo, NULL);
+	r600_resource_reference(&shader->scratch_bo, NULL);
 }