drm: panel: Add orientation support for st7701

Note that this patch is 'heavily inspired' by orientation support in driver
for Elida KD35T133 panel

Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230213153816.213526-4-maccraft123mc@gmail.com