Docs: Update the obsolete requirements for Q_OBJECT and Q_GADGETHEADdev

Since 6.5, you can declare the Q_OBJECT macro in any class section, not
only in private. The docs are updated accordingly. The Q_OBJECT macro
specifies a private section on its own, thus making private all the
members declared after the macro. This is an important behavior change,
so the note about it was rewritten for clarity & moved a little bit up.

Fixes: QTBUG-125776
Pick-to: 6.5 6.6 6.7
Change-Id: Ifba063af7cf7fe7258b6183da5a4599784171052
Reviewed-by: Nicholas Bennett <nicholas.bennett@qt.io>

0 files changed, 0 insertions, 0 deletions