cpu/ rtc/ include/: Remove lingering references to CFG_CMD_* symbols.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/rtc/ds1556.c b/rtc/ds1556.c
index 440d43a..4365cfb 100644
--- a/rtc/ds1556.c
+++ b/rtc/ds1556.c
@@ -203,4 +203,4 @@
 	return (((n / 10) << 4) | (n % 10));
 }
 
-#endif	/* CONFIG_RTC_DS1556 && CFG_CMD_DATE */
+#endif