ath79: sort device definitions in image/*

ath79: sort device definitions in image/*

This applies alphabetic sorting to devices in image/* files.

For certain cases, this patch deviates from strict sorting, e.g.
to ensure that v10 comes after v9.

While at it, fix an indent and remove some useless empty lines.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>