drm/omap: Use {} to zero initialize the mode

drm/omap: Use {} to zero initialize the mode

The first member of drm_display_mode is no longer a structure, but
the code is still using {{0}} to zero initialize it. Make that just
{} so it works regardless of what lies inside.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Fixes: 42acb06b01b1 ("drm: pahole struct drm_display_mode")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200724190718.23567-1-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch.ch>