rtc: Switch to use %ptR

Use %ptR instead of open coded variant to print content of
struct rtc_time in human readable format.

Note, we drop the validation option. This is only used in
a deprecated ABI and is mostly wrong as many RTCs will still be valid
after 2100.

Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 612a83d..e8d77b1 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -368,12 +368,8 @@
 	err = rtc_valid_tm(&alarm->time);
 
 done:
-	if (err) {
-		dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n",
-			alarm->time.tm_year + 1900, alarm->time.tm_mon + 1,
-			alarm->time.tm_mday, alarm->time.tm_hour, alarm->time.tm_min,
-			alarm->time.tm_sec);
-	}
+	if (err)
+		dev_warn(&rtc->dev, "invalid alarm value: %ptR\n", &alarm->time);
 
 	return err;
 }