defconfig: apq8084-perf: add Atheros L1C Gig Ethernet

Add Atheros L1C Gigabit Ethernet dirver compilation
to the APQ8084 perf config. The driver is used on the
8084 platform devices.

Change-Id: Iac2f9070b52868e215f5a4ef84d5213cda6f4f48
Signed-off-by: Ilia Lin <ilialin@codeaurora.org>