transporthandler: LanParam enum -> enum class

We should be using enum classes instead of enums to avoid poluting the
global scope.

Tested:
    Built and run through unit tests.

Change-Id: Iec72f04b5cbf91814d0055c670bcc509eb30a821
Signed-off-by: William A. Kennington III <wak@google.com>
2 files changed