Fixed typo

min.S

@@ -13,7 +13,7 @@ cli
  * The program might work on QEMU without this, but fail on real hardware:
  * http://stackoverflow.com/questions/32508919/how-to-produce-a-minimal-bios-hello-world-boot-sector-with-gcc-that-works-from-a
  *
- * You cannot write immediates direclty to it, must pass through ax:
+ * You cannot write immediates directly to it, must pass through ax:
  * http://stackoverflow.com/questions/19074666/8086-why-cant-we-move-an-immediate-data-into-segment-register
  */
 xor %ax, %ax