Make SW keymaster security level configurable

This CL enables the pure software keymaster implementation to have a
configurable security level, for testing, so we can use it to test
Strongbox features.

Test:  VtsHalKeymasterV4_0TargetTest (on emulator)
Change-Id: I1b012dcd359e294dad7771c7a91e36270d9a0289
(cherry picked from commit 3e99015623ab802dc4cd87ba4083d0150f1af3dc)
4 files changed