libpayload: Add raw_read_ functions

Add: raw_read_cntfrq_el0() and raw_read_cntpct_el0()

Required to support Arch64 Timer

Change-Id: I86aa97039304b9e9336d0146febfe1811c9e075a
Signed-off-by: T Michael Turney <mturney@codeaurora.org>
Reviewed-on: https://review.coreboot.org/25649
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
2 files changed