power: rk3399: Debounce PGOOD_SYS signal
power: rk3399: Debounce PGOOD_SYS signal

PGOOD_SYS may glitch for a period not to exceed 1ms. When PGOOD_SYS or
PGOOD_AP are deasserted, wait for up to 100ms for both signals return
before transitioning out of S0.

BUG=chrome-os-partner:56822
BRANCH=gru
TEST=Manual on kevin, boot device and verify it remains in S0 without
spurious transitions to S3.

Signed-off-by: Shawn Nematbakhsh <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>
Change-Id: I95ccae54fc5939c835f00dc9b7cf88b9d0553c11
Reviewed-on: https://chromium-review.googlesource.com/393148
Reviewed-by: David Schneider <f6dc7060de10912bba612c52f98c21c17bd19e92@chromium.org>
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>
(cherry picked from commit b867d3fc9dea04ac65f5288fb99d3ed65c127644)
Reviewed-on: https://chromium-review.googlesource.com/396139
Commit-Ready: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>
Tested-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@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