mtd: spinand: Add support for ATO25D1GA

Add support for the ATO25D1GA SPI NAND flash.

Datasheet:
- https://atta.szlcsc.com/upload/public/pdf/source/20191212/C469320_04599D67B03B078044EB65FF5AEDDDE9.pdf

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220604113250.4745-1-aidanmacdonald.0x0@gmail.com