drm/ssd130x: Rename commands that are shared across chip families

There are some commands that are shared between the SSD130x and SSD132x
controller families, define these as a common SSD13XX set of commands.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20231014071520.1342189-4-javierm@redhat.com