ARM: kirkwood: add "jedec,spi-nor" flash compatible binding

Starting with commit 8947e396 ("Documentation: dt: mtd: replace
"nor-jedec" binding with "jedec, spi-nor"") we have "jedec,spi-nor"
binding indicating support for JEDEC identification.

Use it for all flashes that are supposed to support READ ID op according
to the datasheets.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>