Fix for fastest optimization with CPU > 120 MHz

WireKinetis.cpp

 	} else {
 		tmp = port().D;
 	}
+#if F_CPU > 120000000
+	__asm__("nop");
+	__asm__("nop");
+	__asm__("nop");
+#endif
 	if (sendStop) port().C1 = I2C_C1_IICEN;
 	rxBufferLength = count;
 	return count;