RFC: kill off ioremap_nocache

[Christoph Hellwig]

Hi all,

with the ioremap changes that did land in 5.5-rc1 ioremap_nocache is
now equal to ioremap for all architectures.  For most architectures
including the common one this has been the case for about 20 years,
but we had a few holdouts.

That means ioremap_nocache is entirely superflous now and can be
killed off.  This series has one big scripted patch to do just that
after a little prep patch to fix up the not entirely obvious mips
definition.

Let me know what you think and if this is something acceptable for
just after -rc1.