usb_pd_protocol: ignore PD resume on enabled port
usb_pd_protocol: ignore PD resume on enabled port

the easiest way to test this is to do multiple "ectool pdcontrol
resume 1" on the AP with a dummy load like a USB flashlight inserted
into the port.  previously, doing a resume on an operational port
would confuse the PD state machine and end up in a SNK_DISCONNECT <->
SNK_DISCONNECT_DEBOUNCE loop.  now, it does nothing.  however,
"ectool pdcontrol suspend 1" follwed by "ectool pdcontrol resume 1"
brings the port down, then brings it back up as expected.

BUG=b:143330980
BRANCH=none
TEST=run multiple "ectool pdcontrol resume 1" commands on AP

Change-Id: Iea5daaf36c8f299c1cb8443fb6892b00c845c517
Signed-off-by: Caveh Jalali <08e24a66aefda7a55ca7d73f8903e0fb16eec763@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1890776
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>
Commit-Queue: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>

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