Address PR feedback.

src/RageSoundReader_Resample_Good.cpp

@@ -110,16 +110,7 @@ namespace
 
 	int GCD( int i1, int i2 )
 	{
-		for(;;)
-		{
-			unsigned iRem = i2 % i1;
-			if( iRem == 0 )
-			{
-				return i1;
-			}
-			i2 = i1;
-			i1 = iRem;
-		}
+		return std::gcd(i1, i2);
 	}
 }