defconfig: arm64: msm: Enable IOMMU test and debug for msm8953

The new IOMMU unit test is useful for performance
profiling of various IOMMU related code paths.
Since there is no overhead in enabling them as
they don't impact performance unless invoked
explicitly, enable them in performance defconfig.

Change-Id: Ia9eb0bd2aa08fb364d028948fd9e967cddb91873
Signed-off-by: Susheel Khiani <skhiani@codeaurora.org>