mtd: rawnand: meson: add support for Amlogic NAND flash controller

Add initial support for the Amlogic NAND flash controller which is
available on Meson SoCs.

Signed-off-by: Liang Yang <liang.yang@amlogic.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Jianxin Pan <jianxin.pan@amlogic.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>