MIPS: bitops: Fix reference to ffz location

Unlike most other architectures, MIPS defines ffz() below ffs().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/bitops.h

@@ -435,7 +435,7 @@ static inline int fls(unsigned int x)
  *
  * This is defined the same way as
  * the libc and compiler builtin ffs routines, therefore
- * differs in spirit from the above ffz (man ffs).
+ * differs in spirit from the below ffz (man ffs).
  */
 static inline int ffs(int word)
 {