DolphinQt: Use input override system for TAS input windows

This lets the TAS input code use a higher-level interface for
overriding inputs instead of having to fiddle with raw bits.
WiiTASInputWindow in particular was messy with how much
controller code it had to re-implement.

Source/Core/DolphinQt/TAS/IRWidget.h

@@ -34,5 +34,7 @@ private:
 };
 
 // Should be part of class but fails to compile on mac os
+static const u16 ir_min_x = 0;
+static const u16 ir_min_y = 0;
 static const u16 ir_max_x = 1023;
 static const u16 ir_max_y = 767;