Fix Final Death Not Showing in Live Fire/Fastball/other round based modes

[EnderBoy9217]

The bug was that the final kill of each round would not show on the scoreboard as a death for the victim.

The regression was introduced in #72 and applied to all round-based gamemodes
Fixes the "Whatever fixed end of round survivors still receiving a death on the scoreboard when round ends, also introduced a bug where the last player killed doesn't receive a death either now." issue made by @GeckoEidechse in #132

Tested in Live Fire and Fastball, also tested in Attrition to make sure it didn't break anything else.
Clearing entities on round end or game end still does not add deaths to scoreboard and everything functions as intended.

[ASpoonPlaysGames]

I think this needs some more testing perhaps.

Looking at the SetWinner code in _gamestate_mp.nut both round based and normal modes enter the WinnerDetermined state, so I'm not sure if this change doesn't have any unintended side-effects

[EnderBoy9217]

I played an Attrition round with this change and it seemed unaffected.
In theory it would count some deaths after the round ends and the screen starts fading to black, however, the game either goes straight to epilogue or fades to black and postmatch shortly afterwards.