rtc: Clean drivers/rtc/Makefile

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/drivers/rtc/ds1306.c b/drivers/rtc/ds1306.c
index 29854fc..12528ed 100644
--- a/drivers/rtc/ds1306.c
+++ b/drivers/rtc/ds1306.c
@@ -36,7 +36,7 @@
 #include <rtc.h>
 #include <spi.h>
 
-#if defined(CONFIG_RTC_DS1306) && defined(CONFIG_CMD_DATE)
+#if defined(CONFIG_CMD_DATE)
 
 #define	RTC_SECONDS		0x00
 #define	RTC_MINUTES		0x01