power/rk3399: Table-based power sequencing
power/rk3399: Table-based power sequencing

We need to refactor power/rk3399.c to make it more flexible
to support different power sequences for upcoming follower boards.

BUG=b:62640322
BRANCH=none
TEST=manaully test on scarlet and kevin:
S0->S3->S0 and S0->S3->S5->G3->S5->S3->S0 work.

Change-Id: I70cdcbaba046bfab4fe832eca58f30524e99e6de
Reviewed-on: https://chromium-review.googlesource.com/540783
Commit-Ready: Philip Chen <3ee404f9ef892bc3fda6e6a76e65843b5fa44db2@chromium.org>
Tested-by: Philip Chen <3ee404f9ef892bc3fda6e6a76e65843b5fa44db2@chromium.org>
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>
Reviewed-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec