uboot-imx

fix incorrect usage of DT node unit address in comments

The DT spec demands a unit-address in a node name to match the "reg"
property in that node. Newer dtc versions will throw warnings if this is
not the case.
Fix all occurences in the tree where node names were mentioned in
comments, to not give bad examples to the reader.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>