These are declared in the ssd130x-i2c transport driver but the information
is not I2C specific, and could be used by other SSD130x transport drivers.

Move them to the ssd130x core driver and just set the OF device entries to
an ID that could be used to lookup the correct device info from an array.

While being there, also move the SSD130X_DATA and SSD130X_COMMAND control
bytes. Since even though they are used by the I2C interface, they could
also be useful for other transport protocols such as SPI.
Suggested-by: Chen-Yu Tsai <wens@kernel.org>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patchwork.freedesktop.org/patch/msgid/20220419214824.335075-5-javierm@redhat.com