ARCH: arm: defconfig: Enable ethernet over SPI

APQ8017 supports ethernet over SPI using
z8851 chip. Make changes to enable all the configs
needed to support ethernet over SPI.

Change-Id: I7d378f26c6c2abc66acac8577b4322ab7ef8eb45
Acked-by: Zakir Syed <zhossain@qti.qualcomm.com>
Signed-off-by: Vijay Navnath Kamble <vkambl@codeaurora.org>
Signed-off-by: Utkarsh Saxena <usaxena@codeaurora.org>