TCPMv2 PE: Fix incorrect response to Not Supported
TCPMv2 PE: Fix incorrect response to Not Supported

Mark modes discovery for an SVID as failed in response to a Not
Supported response from a partner. Don't mark SVIDs discovery (which
already succeeded) as failed.

BUG=none
TEST=make buildall
BRANCH=none

Change-Id: Id218a9108acf2adae8d4c932958ba9b2b299f3eb
Signed-off-by: Abe Levkoy <2e1ad7039298f93262cf06bbb457275fb3e2ecb5@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2238537
Reviewed-by: Diana Z <cb2016afc7183e5356c690dc63b4ba817470501a@chromium.org>

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