ARM: dts: msm: support testbus on gfx smmu for trinket

testbus implementation is different on gfx smmu compared
to apps smmu on trinket so to support testbus on gfx smmu
set qcom,testbus-version to 1.

Change-Id: Ie06b595eda1fd81ca8636b29f9bb48016c3ffd1c
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>