mtd: rawnand: nand_base: support for 'NAND_IS_BOOT_MEDIUM' flag

mtd: rawnand: nand_base: support for 'NAND_IS_BOOT_MEDIUM' flag

Based on Linux kernel:
commit f922bd798bb9 ("mtd: rawnand: add an option to specify NAND chip as a boot device")

Allow to define a NAND chip as a boot device. This can be helpful
for the selection of the ECC algorithm and strength in case the boot
ROM supports only a subset of controller provided options.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
Link: https://lore.kernel.org/r/20240826131710.29746-2-avkrasnov@salutedevices.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>