Keymaster clients need to see all the available devices and figure out
which they want to use. This method finds them all and returns them
in a vector sorted from most secure to least, according to a heuristic
defined in Keymaster::VersionResult::operator<
This CL also makes a few other minor improvements to the support
library, providing more information in VersionResult and adding some
more convenience methods in AuthorizationSetBuilder.
Test: Build & boot
Change-Id: I876238ee9ff72573c30d60e1cec665dd610bcde6
This wrapper was used to manage KM3/KM4 compatibility in keystore.
It's also needed in vold, so this CL moves it here, to make it usable
for vold.
Test: keystore CTS tests
Change-Id: I8079b8577f7d4a8fd67f47fbe1f48861e4a0734b
