staging/easycap: Improve hardware initialization

Sometimes at startup the video urbs consistently and persistently deliver
bad data, each video frame (not isoc frame) containing an excess of
precisely two bytes.  A brute-force cure implemented here is to
repeatedly reinitialize the registers of the SAA7113H chip and the
STK1160 USB bridge until good behaviour is obtained.

Signed-off-by: Mike Thomas <rmthomas@sciolus.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>