media: i2c/ov8865.c: fix error checks using wrong variable

Fix two typos: dvdd -> dovdd and dvdd -> avdd

Both clearly copy-and-paste mistakes.

Fixes this smatch warning:

drivers/media/i2c/ov8865.c:2852 ov8865_probe() warn: passing zero to 'PTR_ERR'

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>