nir/opt_undef: Handle a couple more normal store intrinsics.

They've got the value in the same slot as the others, and the same undef
behavior should be fine.

Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6054>
diff --git a/src/compiler/nir/nir_opt_undef.c b/src/compiler/nir/nir_opt_undef.c
index 0edd7ae..e03e5b8 100644
--- a/src/compiler/nir/nir_opt_undef.c
+++ b/src/compiler/nir/nir_opt_undef.c
@@ -112,6 +112,8 @@
    case nir_intrinsic_store_per_vertex_output:
    case nir_intrinsic_store_ssbo:
    case nir_intrinsic_store_shared:
+   case nir_intrinsic_store_global:
+   case nir_intrinsic_store_scratch:
       arg_index =  0;
       break;
    default: