defconfig: arm/arm64: add smmu config for secure usecases on qcs405

Add the smmu config option that is used for the secure usecases running
on QCS405.

Change-Id: I67d64a9342b62c51e919c7da61e132467b74ce70
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>