media: ov5640: Rework timings programming

The current definition of a sensor mode defines timings as follows:

- hact, vact: Visible width and height
- htot, vtot: Total sizes including blankings

This makes difficult to clearly separate the visible sizes from the
blankings and to make the vertical blanking programmable.

Rework the sensor modes sizes definition to:
- Report the analog crop sizes
- Report the visible crop size
- Report the total pixels per line as HBLANK is fixed
- Report the VBLANK value to make it programmable

Also modify the ov5640_set_timings() function to program all the
windowing registers are remove them from the per-mode register-value
tables.

Do not change the timing values from the ones reported in the register
tables to maintain bisectability.

Signed-off-by: Jacopo Mondi <[email protected]>
Reviewed-by: Laurent Pinchart <[email protected]>
Signed-off-by: Sakari Ailus <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>