media: em28xx: Demote several dev_err to dev_info

These two statements are not errors, reduce to appropriate level.

Signed-off-by: Brad Love <brad@nextdimension.cc>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>