DB/Spell: Fix arcane concentration proc chances

By Ovahlord

sql/updates/world/4.3.4/2017_12_03_01_world.sql

@@ -0,0 +1,7 @@
+--
+DELETE FROM `spell_proc` WHERE `SpellID` IN (-11213, 11213, 12574, 12575);
+INSERT INTO `spell_proc` (`SpellID`, `SpellTypeMask`, `SpellPhaseMask`, `Chance`) VALUES
+(11213, 1, 2, 3),
+(12574, 1, 2, 6),
+(12575, 1, 2, 10);
+