ppc/nx20p348x: Disable VBUS discharge in sink mode
ppc/nx20p348x: Disable VBUS discharge in sink mode

This explicitly disables VBUS discharge when entering sink
mode. According to the vendor, keeping VBUS discharge enabled can cause
some noise and that explains some of the instability we had observed
when charging from another chromebook and 5V3A charger.

BRANCH=none
BUG=b:193211352
TEST=charging from another chromebook is reliable now

Signed-off-by: Caveh Jalali <08e24a66aefda7a55ca7d73f8903e0fb16eec763@chromium.org>
Change-Id: I117dd3f7f9efddce00f903c2b290fa85c6052c5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3044411
Reviewed-by: Denis Brockus <6b21e8190fb5e373363fb95271367073a16474ef@chromium.org>
Commit-Queue: Denis Brockus <6b21e8190fb5e373363fb95271367073a16474ef@chromium.org>

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