arch: remove ioremap_wt, optionally replace with arch_memremap

Now that all call sites for ioremap_wt() have been converted to
memremap(MEMREMAP_WT) we can now proceed with removing the
implementation in the archs.  This amounts to replacing the per-arch
ioremap_wt() implementation with arch_memremap in the case where
ioremap_wt() was actually providing "writethrough" semantics.
Otherwise, ioremap_wt() support that falls back to ioremap() is simply
removed.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
24 files changed