Input: synaptics-rmi4 - fix various V4L2 compliance problems in F54

The v4l2-compliance utility reported several V4L2 API compliance
issues:

- the sequence counter wasn't filled in
- the sequence counter wasn't reset to 0 at the start of streaming
- the returned field value wasn't set to V4L2_FIELD_NONE
- the timestamp wasn't set
- the payload size was undefined if an error was returned
- min_buffers_needed doesn't need to be initialized

Fix these issues.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://lore.kernel.org/r/20191119105118.54285-3-hverkuil-cisco@xs4all.nl
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>