Update getInterfaceVersion checks to include -1

getInterfaceVersion() returns -1 if it is unknown.

V1 of the HAL doesn't implement getInterfaceVersion
due to ABI reasons for regular, unversioned, AIDL
interfaces.

Bug: 206670536
Test: on device
Change-Id: Id63b65b8a03488a6f179c7f64bd9d457e28eb30a