This freezes the interface as of the latest beta build, although it has
not changed since then.
This change adds the necessary implementations for getInterfaceVersion.
Test: flashed, WiFi working
Bug: 128803828
Merged-In: Ib852b0555f0e20b858f9dd0b16dbd98dbbd22b55
Merged-In: I0c231bdce89474b53603cc15d55787c8c78a809d
(cherry picked from commit fd4eafe8f6)
Change-Id: Idc0e7ea98dbf57e07ee578bc1772c2111af2e563