The converters need to be instantiated (which implicitly registers)
after QPA has been initialized, i.e. after QGuiApplication has been
instantiated. Clarify this in the documentation of the types.
Remove the dead documentation for the explicit registration function.
The API does not exist, and the documentation was never generated for
Qt 6 either. The function does not need to be called as long as new mime
converters are instantiated correctly (after QPA was initialized).
Pick-to: 6.6 6.5
Task-number: QTBUG-119216
Change-Id: I4e31b3773e88f7a6d579265f093bab46847cb028
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
0b60450eee