reef: change USB_C0_PD_INT voltage tolerance
reef: change USB_C0_PD_INT voltage tolerance

The USB_C0_PD_INT signal is actually at 3.3V levels. Don't mark
the voltage sensitivity to 1.8V.

BUG=chrome-os-partner:53035
BRANCH=None
TEST=Rachel ran with resulting image. Nothing bad observed.

Change-Id: I36bc3f911b715dc967cc8f23dfc70c3d0e5023d2
Signed-off-by: Aaron Durbin <af0622ab041e8b0f8e5819838dcc93898196e71f@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/346734
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