[committed] Convert xstormy16 to LRA

[Hans-Peter Nilsson]

> From: Hans-Peter Nilsson <hp@axis.com>
> Date: Fri, 12 May 2023 15:53:49 +0200

> Anyway, Roger mentioned that the clobbers emitted by the
> lower-subreg passes were apparently damaging, so I'll try
> this out "for fun", on the assumption that they're actually
> unnecessary.  I don't think actually removing them has been
> attempted?

> --- lower-subreg.cc.orig	2023-04-29 02:53:39.000000000 +0200
> +++ lower-subreg.cc	2023-05-12 15:35:25.574668930 +0200

Bah, then I noticed r14-554-gd8a6945c6ea22e, committed
several days ago.  I should have checked up-to-date sources...
Thanks Roger!

Now off to measure the impact.  Maybe up to par with reload
now? :)

brgds, H-P