ARM: bcm2835: Switch to use %ptT

Use %ptT instead of open coded variant to print content of
time64_t type in human readable format.

Link: https://lore.kernel.org/r/20200415170046.33374-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Rewieved-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>

drivers/firmware/raspberrypi.c

@@ -182,16 +182,10 @@ rpi_firmware_print_firmware_revision(struct rpi_firmware *fw)
 					RPI_FIRMWARE_GET_FIRMWARE_REVISION,
 					&packet, sizeof(packet));
 
-	if (ret == 0) {
-		struct tm tm;
-
-		time64_to_tm(packet, 0, &tm);
+	if (ret)
+		return;
 
-		dev_info(fw->cl.dev,
-			 "Attached to firmware from %04ld-%02d-%02d %02d:%02d\n",
-			 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
-			 tm.tm_hour, tm.tm_min);
-	}
+	dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &packet);
 }
 
 static void