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

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/cpu/i386/serial.c b/cpu/i386/serial.c
index 4933d23..baf35e5 100644
--- a/cpu/i386/serial.c
+++ b/cpu/i386/serial.c
@@ -500,4 +500,4 @@
 	return;
 }
 #endif	/* (CONFIG_KGDB_SER_INDEX & 2) */
-#endif	/* CFG_CMD_KGDB */
+#endif