coffeecake: Set usb output voltage back to 5V on a power supply reset
coffeecake: Set usb output voltage back to 5V on a power supply reset

This will prevent not allowed voltages (9V) applied on Vbus on initial
attach, where the voltage needs to be vSafe5V.

Signed-off-by: Benson Leung <bleung@chromium.org>

BRANCH=none
BUG=b:67910051
TEST=Plug in Yeeco loader, then walleye, then Yeeco loader. Confirm
5V when loader is attached.

Change-Id: Ic9d40b093d96a4eb8a7ac4649701269f7f55bb33
Reviewed-on: https://chromium-review.googlesource.com/724270
Commit-Ready: Rong Chang <3a05493f7adfb36d203f663b3bc2ba30e9d6284f@chromium.org>
Tested-by: Rong Chang <3a05493f7adfb36d203f663b3bc2ba30e9d6284f@chromium.org>
Reviewed-by: Rong Chang <3a05493f7adfb36d203f663b3bc2ba30e9d6284f@chromium.org>

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