backuptool_ab: Pick LineageOS properties from build.prop

 * The LineageOS versions properties were removed from the build.prop,
    which is resolved properly in commit:
    "lineage: Keep LineageOS versions properties in build.prop"
    Change-Id: I0060141c097b3d14c3710eee1e0caf7110634967

Change-Id: Ib11670474641d6fd14a00f8421e9fe8d1879bbc2