drm/panel: simple: Add missing connector type and pixel format for AUO T215HVN01

The connector type and pixel format are missing for this panel,
add them to prevent various drivers from failing to determine
either of those parameters.

Fixes: 7ee933a1 ("drm/panel: simple: Add support for AUO T215HVN01")
Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230709134914.449328-1-marex@denx.de