media: ov772x: Replace msleep(1) with usleep_range

msleep() can sleep up to 20ms.

As suggested by Documentation/timers/timers_howto.txt replace it with
usleep_range() with up to 5ms delay.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>