V4L/DVB (8845): s2255drv: adds JPEG compression quality control

adds VIDIOC_S_JPEGCOMP and VIDIOC_G_JPEGCOMP ioctls for
controlling JPEG compression quality.

Signed-off-by: Dean Anderson <dean@sensoray.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>