Simplify suicide logic (#798)

Refactor suicide logic to be simpler.

scripting/get5/stats.sp

@@ -709,11 +709,11 @@ public Action Stats_PlayerDeathEvent(Event event, const char[] name, bool dontBr
   // fall damage is weapon id 0, attacker 0, weapon "worldspawn"
   // falling from vertigo is attacker 0, weapon id 0, weapon "trigger_hurt"
   // c4 is attacker 0, weapon id 0, weapon planted_c4
-  // with those in mind, we can determine suicide from this:
-  bool killedByBomb = StrEqual("planted_c4", weapon, true);
-  // Unfortunately molotovs are also weapon id 0, so we have to *not* consider that a suicide unless attacker == victim.
-  bool killedByMolotov = StrEqual("inferno", weapon, true);
-  bool isSuicide = !killedByBomb && (attacker == victim || (view_as<int>(weaponId) == 0 && !killedByMolotov));
+  // killing self with weapons is attacker == victim
+  // some weapons, such as unsilenced USP or M4A1S and molotov fire are also weapon 0, so weapon ID is unreliable.
+  // with those in mind, we can determine that suicide must be true if attacker is 0 or attacker == victim and it was **not** the bomb.
+  bool killedByBomb = StrEqual("planted_c4", weapon);
+  bool isSuicide = (!validAttacker || attacker == victim) && !killedByBomb;
 
   IncrementPlayerStat(victim, STAT_DEATHS);
   // used for calculating round KAST
@@ -727,7 +727,7 @@ public Action Stats_PlayerDeathEvent(Event event, const char[] name, bool dontBr
 
   if (isSuicide) {
     IncrementPlayerStat(victim, STAT_SUICIDES);
-  } else if (!killedByBomb && validAttacker) {
+  } else if (!killedByBomb) {
     if (attackerTeam == victimTeam) {
       IncrementPlayerStat(attacker, STAT_TEAMKILLS);
     } else {