Lars: Refactoring PD port count setting
Lars: Refactoring PD port count setting

usb_pd_policy.c : update & remove duplicate code

BUG=None
BRANCH=lars
TEST=`make BOARD=lars -j`, OS can boot up normally

Change-Id: I82729edf89b6ce719c8f6897b877ee57ee0daefe
Signed-off-by: Ryan Zhang <50a92783d595cae957ab2a2aa8dfe1aa1d9433fd@quantatw.com>
Reviewed-on: https://chromium-review.googlesource.com/315030
Commit-Ready: 志偉 黃 <10e3d900b2f3b4520c53f0984b76449e42c440ff@quantatw.com>
Tested-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>
Reviewed-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>

akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec