cpufreq: davinci: Fix clk use after free

The remove function first frees the clks and only then calls
cpufreq_unregister_driver(). If one of the cpufreq callbacks is called
just before cpufreq_unregister_driver() is run, the freed clks might be
used.

Fixes: 6601b803 ("davinci: add generic CPUFreq driver for DaVinci")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/cpufreq/davinci-cpufreq.c

@@ -133,13 +133,13 @@ static int __init davinci_cpufreq_probe(struct platform_device *pdev)
 
 static int __exit davinci_cpufreq_remove(struct platform_device *pdev)
 {
+	cpufreq_unregister_driver(&davinci_driver);
+
 	clk_put(cpufreq.armclk);
 
 	if (cpufreq.asyncclk)
 		clk_put(cpufreq.asyncclk);
 
-	cpufreq_unregister_driver(&davinci_driver);
-
 	return 0;
 }