Try to use video-filter instead of vout-filter for deinterlacing.
It only works for blend and X mode but there are probably the most used.
When blend/X are enabled/disabled:
- It avoids recreating the vout.
- It avoids deinterlacing the (soft) subtitles.
The other modes are not possible without a lot of vout works, so it is
postponed for later.
As a side effect, the initial value of the menu now takes into account the
command line options.
Please, report any regression. This code is made complicated by the
vout filter/video filter2 switches&tricks.