rtc: Clean drivers/rtc/Makefile

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 2e0c118..2af3ee5 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -27,35 +27,35 @@
 
 LIB	= $(obj)librtc.a
 
-COBJS-y += bfin_rtc.o
+COBJS-$(CONFIG_RTC_BFIN) += bfin_rtc.o
 COBJS-y += date.o
-COBJS-y += ds12887.o
-COBJS-y += ds1302.o
-COBJS-y += ds1306.o
-COBJS-y += ds1307.o
-COBJS-y += ds1337.o
-COBJS-y += ds1374.o
-COBJS-y += ds1556.o
-COBJS-y += ds164x.o
-COBJS-y += ds174x.o
-COBJS-y += ds3231.o
+COBJS-$(CONFIG_RTC_DS12887) += ds12887.o
+COBJS-$(CONFIG_RTC_DS1302) += ds1302.o
+COBJS-$(CONFIG_RTC_DS1306) += ds1306.o
+COBJS-$(CONFIG_RTC_DS1307 || CONFIG_RTC_DS1338) += ds1307.o
+COBJS-$(CONFIG_RTC_DS1337) += ds1337.o
+COBJS-$(CONFIG_RTC_DS1374) += ds1374.o
+COBJS-$(CONFIG_RTC_DS1556) += ds1556.o
+COBJS-$(CONFIG_RTC_DS164x) += ds164x.o
+COBJS-$(CONFIG_RTC_DS174x) += ds174x.o
+COBJS-$(CONFIG_RTC_DS3231) += ds3231.o
 COBJS-$(CONFIG_RTC_ISL1208) += isl1208.o
-COBJS-y += m41t11.o
-COBJS-y += m41t60.o
+COBJS-$(CONFIG_RTC_M41T11) += m41t11.o
+COBJS-$(CONFIG_RTC_M41T60) += m41t60.o
 COBJS-$(CONFIG_RTC_M41T62) += m41t62.o
-COBJS-y += m48t35ax.o
-COBJS-y += max6900.o
+COBJS-$(CONFIG_RTC_M48T35A) += m48t35ax.o
+COBJS-$(CONFIG_RTC_MAX6900) += max6900.o
 COBJS-$(CONFIG_RTC_MC13783) += mc13783-rtc.o
-COBJS-y += mc146818.o
-COBJS-y += mcfrtc.o
-COBJS-y += mk48t59.o
-COBJS-y += mpc5xxx.o
-COBJS-y += mpc8xx.o
-COBJS-y += pcf8563.o
-COBJS-y += rs5c372.o
-COBJS-y += rx8025.o
-COBJS-y += s3c24x0_rtc.o
-COBJS-y += x1205.o
+COBJS-$(CONFIG_RTC_MC146818) += mc146818.o
+COBJS-$(CONFIG_MCFRTC) += mcfrtc.o
+COBJS-$(CONFIG_RTC_MK48T59) += mk48t59.o
+COBJS-$(CONFIG_RTC_MPC5200) += mpc5xxx.o
+COBJS-$(CONFIG_RTC_MPC8xx) += mpc8xx.o
+COBJS-$(CONFIG_RTC_PCF8563) += pcf8563.o
+COBJS-$(CONFIG_RTC_RS5C372A) += rs5c372.o
+COBJS-$(CONFIG_RTC_RX8025) += rx8025.o
+COBJS-$(CONFIG_RTC_S3C24X0) += s3c24x0_rtc.o
+COBJS-$(CONFIG_RTC_X1205) += x1205.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)