ARM: dts: Add qcom,cnss for WLAN on vplatform msm8996_gvmq

The device tree node qcom,cnss includes all WLAN related hardware
configurations including power supply regulators and pinctrl
configuration etc.  So, add qcom,cnss into the dts of Linux/Android
virtual platform msm8996_gvmq to enable WLAN over PCIe.

Change-Id: I0dbefbeefb7c6e843e55f32a8b33c4113a3a2e6e
Signed-off-by: Ferry Zhou <tianguiz@codeaurora.org>