media: i2c: Use dev_err_probe() in ov8865

There is a chance that regulator_get() returns -EPROBE_DEFER, in which
case printing an error message is undesirable. To avoid spurious messages
in dmesg in the event that -EPROBE_DEFER is returned, use dev_err_probe()
on error paths for regulator_get().

Signed-off-by: Daniel Scally <djrscally@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>