Allow to enable/disable memory checks even on release mode through the flag, return error for invalid addresses on SvcMap*Memory svcs, do not return error on SvcQueryMemory (instead, return reserved for the end of the address space), other minor tweaks

Ryujinx.Tests/Cpu/CpuTest.cs

@@ -47,7 +47,7 @@ namespace Ryujinx.Tests.Cpu
 
         protected void Opcode(uint Opcode)
         {
-            Thread.Memory.WriteUInt32(Position, Opcode);
+            Thread.Memory.WriteUInt32Unchecked(Position, Opcode);
             Position += 4;
         }