spi/rtc-{ds1390,ds3234,m41t94}: Use spi_get_drvdata() for SPI devices

The recently increased type checking in platform_get_drvdata() reveals a few
offenders:

drivers/rtc/rtc-ds1390.c:161: warning: passing argument 1 of ‘platform_get_drvdata’ from incompatible pointer type
drivers/rtc/rtc-ds3234.c:161: warning: passing argument 1 of ‘platform_get_drvdata’ from incompatible pointer type
drivers/rtc/rtc-m41t94.c:139: warning: passing argument 1 of ‘platform_get_drvdata’ from incompatible pointer type

Use spi_get_drvdata() instead of platform_get_drvdata().
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

drivers/rtc/rtc-ds1390.c

@@ -158,7 +158,7 @@ static int __devinit ds1390_probe(struct spi_device *spi)
 
 static int __devexit ds1390_remove(struct spi_device *spi)
 {
-	struct ds1390 *chip = platform_get_drvdata(spi);
+	struct ds1390 *chip = spi_get_drvdata(spi);
 
 	rtc_device_unregister(chip->rtc);
 	kfree(chip);

drivers/rtc/rtc-ds3234.c

@@ -158,7 +158,7 @@ static int __devinit ds3234_probe(struct spi_device *spi)
 
 static int __devexit ds3234_remove(struct spi_device *spi)
 {
-	struct rtc_device *rtc = platform_get_drvdata(spi);
+	struct rtc_device *rtc = spi_get_drvdata(spi);
 
 	rtc_device_unregister(rtc);
 	return 0;

drivers/rtc/rtc-m41t94.c

@@ -136,7 +136,7 @@ static int __devinit m41t94_probe(struct spi_device *spi)
 
 static int __devexit m41t94_remove(struct spi_device *spi)
 {
-	struct rtc_device *rtc = platform_get_drvdata(spi);
+	struct rtc_device *rtc = spi_get_drvdata(spi);
 
 	if (rtc)
 		rtc_device_unregister(rtc);