Core/Misc: Fix issues reported by static analysis

Coverity defect IDs: 1023036, 1022620

src/server/game/Entities/Unit/Unit.cpp

@@ -5930,7 +5930,7 @@ bool Unit::HandleDummyAuraProc(Unit* victim, uint32 damage, AuraEffect* triggere
                 case 55677:
                 {
                     // Dispel Magic shares spellfamilyflag with abolish disease
-                    if (procSpell->SpellIconID != 74)
+                    if (!procSpell || procSpell->SpellIconID != 74)
                         return false;
                     if (!target || !target->IsFriendlyTo(this))
                         return false;