tests: Successful invoke of pd_get_amode cmd
tests: Successful invoke of pd_get_amode cmd

Verify that invoking the EC host command EC_CMD_USB_PD_GET_AMODE has a
successful return code and the response size is unchanged.

BRANCH=none
BUG=b:219562077
TEST=zmake test test-drivers

Signed-off-by: Aaron Massey <79529a820df71f45023239a3663736629646cc34@google.com>
Change-Id: Icd29c921c0c080aeff1316bfa7b211d63687f9fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3687085
Reviewed-by: Wai-Hong Tam <04b587fdf5845741a0c5a8b9cd59ca72d73ef8fc@google.com>

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