trusty: SCS: make kernel support dependent on USER_SCS_SUPPORTED am: e5eb28a4ec

Original change: https://android-review.googlesource.com/c/trusty/lk/trusty/+/2846257

Change-Id: I505bcaf61ce6f9f0d3a68f93077ace9ba3cf2f64
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>