Directory naming issue for Windows in mpfs-usb-host-hid example

[hughbreslin]

The mpfs-usb-host-hid example contains two copies of the Core10gBaseKR_PHY drivers, one with a lower case "g" and one uppercase. This causes clone/checkout of the bare metal examples repo to fail as there are conflicting file names as windows is case insensitive.

I.e:

Core10gBaseKR_PHY
Core10GBaseKR_PHY

resolve to the same name on Windows. This can be seen here.

Please remove the unused version of the drivers.