Revert "arm64: errata: Workaround possible Cortex-A715 [ESR|FAR]_ELx corruption"

This reverts commit 44ecda71.

All versions of this patch on the mailing list, including the version
that ended up getting merged, have portions of code guarded by the
non-existent CONFIG_ARM64_WORKAROUND_2645198 option. Although Anshuman
says he tested the code with some additional debug changes [1], I'm
hesitant to fix the CONFIG option and light up a bunch of code right
before I (and others) disappear for the end of year holidays, during
which time we won't be around to deal with any fallout.

So revert the change for now. We can bring back a fixed, tested version
for a later -rc when folks are thinking about things other than trees
and turkeys.

[1] https://lore.kernel.org/r/b6f61241-e436-5db1-1053-3b441080b8d6@arm.com


Reported-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20221215094811.23188-1-lukas.bulwahn@gmail.com


Signed-off-by: Will Deacon <will@kernel.org>