feat(cpus): add more errata framework helpers

Figuring out the naming format of errata is annoying, so add a shorthand
for the custom checker functions. Also add some more semantic macros
instead of passing around constants.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: Ibdcf72146738026df4ebd047bfb30790fd4a1053
(cherry picked from commit 94a75ad456a8bda75ca1e4343f00be249a201a69)
2 files changed