UBUNTU: SAUCE: arm64: arch_timer: Add infrastructure for multiple erratum detection...

UBUNTU: SAUCE: arm64: arch_timer: Add infrastructure for multiple erratum detection methods

BugLink: https://bugs.launchpad.net/bugs/1675509
We're currently stuck with DT when it comes to handling errata, which
is pretty restrictive. In order to make things more flexible, let's
introduce an infrastructure that could support alternative discovery
methods. No change in functionality.

Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 180cb954f2b26c6bccfd1a1229e6bb7c8fb07167
 in the timers/errata-rework branch of
 git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>