It's much easier to figure out why the SDVO encoder refuses to cooperate
if we can see what status we got back.

v2: Zero initialize only the first character, not the whole buffer
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20190410170941.28142-1-ville.syrjala@linux.intel.com