oak: increase the PMIC power key press time to 5 seconds.
oak: increase the PMIC power key press time to 5 seconds.

There are 3 methods to power on the system:
1) Pulling PWRKEY low (User presses PWRKEY)
2) Setting BBWAKEUP high
3) Valid charger plug-in
We should ensure that BBWAKEUP should be high when release PWRKEY.
Due to the RTC driver of coreboot will move to ramstage, and the
setup timing of BBWAKEUP will be postpone. In order to ensure PMIC
keeping the power until coreboot pull BBWAKEUP up, it needs to
increase the PMIC power key press time to avoid PMIC turn the
power off. This change is related to:
https://chromium-review.googlesource.com/#/c/257389/

BRANCH=none
BUG=none
TEST=manual
Update coreboot with above patch, press power key and system
should power on normally.

Change-Id: I7fabc49e0b3956885cb83a0b40c31c60080d0cbc
Signed-off-by: Ben Lok <310171a828df105188e0b545d65d6370e8133283@mediatek.com>
Reviewed-on: https://chromium-review.googlesource.com/290538
Reviewed-by: Rong Chang <3a05493f7adfb36d203f663b3bc2ba30e9d6284f@chromium.org>

fourier49/BIZ_EC,fourier49/BIZ_EC,fourier49/BIZ_EC,fourier49/BIZ_EC