ARM: dts: msm: Add dummy gpios for display for sdm670 and sdm710 platforms

AQT1000 codec uses Tertiary MI2S as backend. Tertiary MI2S
uses same gpios as display driver. Thus hard-reset display and
use dummy gpios for display so that gpio conflict is avoided.

CRs-Fixed: 2180664
Change-Id: I12ca08e86f71dcbe587edcf289fb7403ed597ca5
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>