Now that the cea mode handling is not 100% tied to the single
array the dummy VIC 0 mode is pretty much pointles. Throw it
out.

v2: Rebase

Cc: Tom Anderson <thomasanderson@google.com>
Cc: Hans Verkuil <hansverk@cisco.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191213174348.27261-4-ville.syrjala@linux.intel.comReviewed-by: NThomas Anderson <thomasanderson@google.com>