ICU-22968 Rearrange bits in trie values in normalization data export for ICU4X

[hsivonen]

This changes the format of the normalization data export for ICU4X in the way expected by unicode-org/icu4x#5813 , which makes the ICU4X normalizer significantly faster.

Checklist

• Required: Issue filed: https://unicode-org.atlassian.net/browse/ICU-22968
• Required: The PR title must be prefixed with a JIRA Issue number. Example: "ICU-1234 Fix xyz"
• Required: The PR description must include the link to the Jira Issue, for example by completing the URL in the first checklist item
• Required: Each commit message must be prefixed with a JIRA Issue number. Example: "ICU-1234 Fix xyz"
• Issue accepted (done by Technical Committee after discussion)
• Tests included, if applicable
• API docs and/or User Guide docs changed or added, if applicable