platform/x86: gigabyte-wmi: Add Z690M AORUS ELITE AX DDR4 support

Add dmi_system_id of Gigabyte Z690M AORUS ELITE AX DDR4 board.
Tested on my PC.

Signed-off-by: Piotr Chmura <chmooreck@gmail.com>
Link: https://lore.kernel.org/r/bd83567e-ebf5-0b31-074b-5f6dc7f7c147@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>