x86/pci: Remove old STA2x11 support

ST ConneXt STA2x11 was an interface chip for Atom E6xx processors,
using a number of components usually found on Arm SoCs. Most of this
was merged upstream, but it was never complete enough to actually work
and has been abandoned for many years.

We already had an agreement on removing it in 2022, but nobody ever
submitted the patch to do it.

Without STA2x11, CONFIG_X86_32_NON_STANDARD no longer has any
use - remove it.

Suggested-by: Davide Ciminaghi <ciminaghi@gnudd.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250226213714.4040853-10-arnd@kernel.org