[media] vb2: split the io_flags member of vb2_queue into a bit field

This patch splits the io_flags member of vb2_queue into a bit field.
Instead of an enum with flags separate bit fields were introduced.

Signed-off-by: Kamil Debski <k.debski@samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>