nls: delete two compose sequences with an anomalous post-fixed breve

Two years ago, commit b126bfd7 allowed using also a lowercase u wherever an uppercase U was used to represent a breve. But the commit should have limited itself to only the prefixed uses of U, as that is how most letters with a breve are composed.

Also, group the two compose sequences with an uppercase post-fixed U together with the corresponding other post-fixed sequences.

Signed-off-by: Benno Schulenberg bensberg@telfort.nl