iommu: msm: Refactor remote spinlock defconfig

Refactor the remote spinlock defconfig to allow it to be used with
subsystems other than GPU. This will enhance the usability of this
feature and minimize the chance of errors when enabling this feature.

CRs-fixed: 517873
Change-Id: I609cd77ece4e8d2e15e1a24d87a23be05a61b60f
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>