media: ov5640: Fix soft reset sequence and timings

Move the register-based reset out of the init_setting[] and into the
powerup_sequence function. The sensor is power cycled and reset using
the gpio pins so the soft reset is not always necessary.

This also ensures that soft reset honors the timing sequence
from the datasheet [1].

[1] https://cdn.sparkfun.com/datasheets/Sensors/LightImaging/OV5640_datasheet.pdf



Fixes: 19a81c14 ("[media] add Omnivision OV5640 sensor driver")
Reported-by: Nishanth Menon <nm@ti.com>
Suggested-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Jai Luthra <j-luthra@ti.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonaboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>