Relax APF version check in ApfGenerator

Instead of requiring an *exact* version, we now require a minimum
version. This is necessary if we wish to upgrade the APF interpreter in
vendor firmware independently of the framework code. Adding new opcodes
without changing the semantics of the old ones is always possible and
usually easy, so we can at least have a backwards-compatibility horizon
wider than a single version.

Change-Id: I4f1ed661afb2ede193188eb8086fbf2a8b45b33d
Test: Change extracted from aosp/647079 and tested there