ARM: dts: msm: update DSI phy T_TA_GO setting for sdm670

Current value of DSI phy T_TA_GO does not follow MIPI specification
properly. Hence update the setting as per HW recommendation for
sdm670 platform.

Change-Id: I1789fc705858d4979b2439f09adacd183018908a
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>