drivers/rtc/rtc-tegra.c: properly initialize spinlock

Using __SPIN_LOCK_UNLOCKED for a dynamically allocated lock is wrong and
breaks the build with PREEMPT_RT_FULL.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Andrew Chew <achew@nvidia.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-tegra.c

@@ -343,7 +343,7 @@ static int __devinit tegra_rtc_probe(struct platform_device *pdev)
 
 	/* set context info. */
 	info->pdev = pdev;
-	info->tegra_rtc_lock = __SPIN_LOCK_UNLOCKED(info->tegra_rtc_lock);
+	spin_lock_init(&info->tegra_rtc_lock);
 
 	platform_set_drvdata(pdev, info);