mtd: nand: omap2: check for elm_id removed

[Teresa Remmet]

Hello,

with commit c9711ec5250b22fd94e9b34c17c095e001a90e66
("mtd: nand: omap: Clean up device tree support")
the old "elm_id" property check has been removed. So only "ti,elm-id" is
valid now.
I noticed that the old property is still used by 3 boards:

git grep elm_id arch/arm/boot/dts/*
arch/arm/boot/dts/am335x-baltos.dtsi:           elm_id = <&elm>;
arch/arm/boot/dts/am335x-igep0033.dtsi:         elm_id = <&elm>;
arch/arm/boot/dts/am335x-phycore-som.dtsi:              elm_id = <&elm>;

I wonder if the right way would be to patch the device trees, or to add
the check again and to keep backward compatibility?

I may provide a patch then.

Regards,
Teresa