Cleanup: fix "MHz" spelling

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/freescale/mpc8540ads/mpc8540ads.c b/board/freescale/mpc8540ads/mpc8540ads.c
index 7dccd37..a0b6fbd 100644
--- a/board/freescale/mpc8540ads/mpc8540ads.c
+++ b/board/freescale/mpc8540ads/mpc8540ads.c
@@ -127,8 +127,8 @@
 	 * Errata LBC11.
 	 * Fix Local Bus clock glitch when DLL is enabled.
 	 *
-	 * If localbus freq is < 66Mhz, DLL bypass mode must be used.
-	 * If localbus freq is > 133Mhz, DLL can be safely enabled.
+	 * If localbus freq is < 66MHz, DLL bypass mode must be used.
+	 * If localbus freq is > 133MHz, DLL can be safely enabled.
 	 * Between 66 and 133, the DLL is enabled with an override workaround.
 	 */