Cleanup: fix "MHz" spelling

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/board/pm854/pm854.c b/board/pm854/pm854.c
index db855df..fed0ed4 100644
--- a/board/pm854/pm854.c
+++ b/board/pm854/pm854.c
@@ -144,8 +144,8 @@
 	 * 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.
 	 */