radeonsi: stop leaking nir

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
diff --git a/src/gallium/drivers/radeonsi/si_state_shaders.c b/src/gallium/drivers/radeonsi/si_state_shaders.c
index 35bc0db..71d7987 100644
--- a/src/gallium/drivers/radeonsi/si_state_shaders.c
+++ b/src/gallium/drivers/radeonsi/si_state_shaders.c
@@ -2484,6 +2484,7 @@
 	util_queue_fence_destroy(&sel->ready);
 	mtx_destroy(&sel->mutex);
 	free(sel->tokens);
+	ralloc_free(sel->nir);
 	free(sel);
 }