cpufreq: cpufreq-cpu0: Use devm_regulator_get_optional()

Since the cpufreq-cpu0 driver is capable of coping without a software
controllable regulator and would be confused by a dummy one it should
use devm_regulator_get_optional() to ensure no dummy is provided.

Signed-off-by: Mark Brown <broonie@linaro.org>
1 file changed