defconfig: arm: msm: Enable MSM_TZ_SMMU for msmtitanium

We need to enable CONFIG_MSM_TZ_SMMU option
as we would be calling into TZ for configuring
GFX QSMMU

Change-Id: If3c9be15e3ccde2dee8f174cd6f7ed1cc478ad1e
Signed-off-by: Susheel Khiani <skhiani@codeaurora.org>