Spell/Unit: Fix default for coefficient being 0 and fix coeff for npc…

… pets

Closes cmangos/issues#3685

again

src/game/Entities/Unit.cpp

@@ -6899,11 +6899,9 @@ void Unit::EnergizeBySpell(Unit* victim, SpellEntry const* spellInfo, uint32 dam
  */
 int32 Unit::SpellBonusWithCoeffs(SpellEntry const* spellProto, SpellEffectIndex effectIndex, int32 total, int32 benefit, int32 ap_benefit,  DamageEffectType damagetype, bool donePart)
 {
-    // Distribute Damage over multiple effects, reduce by AoE
-    float coeff = 1.0f;
-
-    // Not apply this to creature casted spells
-    if (GetTypeId() == TYPEID_UNIT && !((Creature*)this)->IsPet())
+    float coeff = 0.f; // no coefficient by default
+    // does not apply to creatures
+    if (IsCreature() && !IsPlayerControlled())
         coeff = 1.0f;
     // Check for table values
     if (spellProto->effectBonusCoefficient[effectIndex] > 0 || spellProto->effectBonusCoefficientFromAP[effectIndex] > 0)