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

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/include/_exports.h b/include/_exports.h
index eeb65f4..a0fbf2a 100644
--- a/include/_exports.h
+++ b/include/_exports.h
@@ -18,4 +18,4 @@
 #if defined(CONFIG_CMD_I2C)
 EXPORT_FUNC(i2c_write)
 EXPORT_FUNC(i2c_read)
-#endif	/* CFG_CMD_I2C */
+#endif