As per Documentation/timers/timers-howto.txt Msleep < 20ms can sleep for
up to 20ms. so use usleep_range.
Signed-off-by: Mohan Kumar <mohankumar718@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>