gamedata: add verified EncodeField linux signature (Register no longer fails)

The file was refs-only after I stripped the placeholder sigs -> GameData.Register threw
'no valid gamedata for linux' (caught, non-fatal). Added the verified EncodeField prologue
signature (true entry 0x4334d0) so Register succeeds + the address resolves via gamedata too.
Dropped the two refs-only entries (resolved at runtime via FindString/RE, not gamedata).