mtd: rawnand: gpmi: Use a single line for of_device_id

The .compatible and .data pairs can be stored in a single line, which
makes the code more concise.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201208221243.3255-1-festevam@gmail.com