st/mesa: lower global vars to local after lowering clip

st/mesa: lower global vars to local after lowering clip

When this code was merged, this wasn't necessary because the
state-tracker would do it later anyway. But this recently got changed,
without changing the code that depended on this.

Arguably, this was a mistake in the lowering pass to begin with. Either
way, let's fix it by not assuming that the lowering code gets called
later when it's not needed.

This fixed user-defined clip-planes in Zink.

Signed-off-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Fixes: eaffdad1082 ("st/mesa: don't lower_global_vars_to_local for VS if there are no dead inputs")
Reviewed-by: Marek Olšák <marek.olsak@amd.com>