spi: spidev: Add an entry for elgin,jg10309-01

The rv1108-elgin-r1 board has an LCD controlled via SPI in userspace.
The marking on the LCD is JG10309-01.

Add the "elgin,jg10309-01" compatible string.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20240828180057.3167190-2-festevam@gmail.com


Signed-off-by: Mark Brown <broonie@kernel.org>