There's a script, update_moc.sh, and a set of patches to be applied on top of the qtbase moc source for use in qscxmlc. This doesn't seem to have been run for quite some time, because the patches don't apply cleanly. There are major conflicts.

Acceptance criteria:

• the moc copy is in sync with qtbase again
  • (probably in all supported branches, cf. QTBUG-109541)
• patch files are updated
• updating moc copy in qtscxml is registered as part of the release process