defconfig: arm64: Enable USB Electrical and Link test support on kona

Enable EHSET Test fixture driver to perform the high speed electrical
testing procedure for USB-IF compliance. Also enable the Link Layer
Test driver to allow for SuperSpeed link layer testing.

Change-Id: Ic92c28dd30b2d5f00278303727a6586b0375c691
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>