Fix allocation of multiple effect slots, effects, and filters

OpenAL32/alAuxEffectSlot.c

@@ -76,6 +76,8 @@ AL_API ALvoid AL_APIENTRY alGenAuxiliaryEffectSlots(ALsizei n, ALuint *effectslo
 
                     Context->AuxiliaryEffectSlotCount++;
                     i++;
+
+                    list = &(*list)->next;
                 }
             }
         }

OpenAL32/alEffect.c

@@ -71,6 +71,8 @@ AL_API ALvoid AL_APIENTRY alGenEffects(ALsizei n, ALuint *effects)
                 InitEffectParams(*list, AL_EFFECT_NULL);
                 g_EffectCount++;
                 i++;
+
+                list = &(*list)->next;
             }
         }
     }

OpenAL32/alFilter.c

@@ -71,6 +71,8 @@ AL_API ALvoid AL_APIENTRY alGenFilters(ALsizei n, ALuint *filters)
                 InitFilterParams(*list, AL_FILTER_NULL);
                 g_FilterCount++;
                 i++;
+
+                list = &(*list)->next;
             }
         }
     }