drm/tidss: drop use of legacy drm_bus_flags

Use the more descriptive _DRIVE_ variants thus avoiding the
legacy drm_bus_flags values.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200630180545.1132217-2-sam@ravnborg.org