Enable Strict Mode 6.12 in qtimageformats


Was mostly there using the individual macros. This newly includes only
QT_NO_DISCONNECT_CONST_CONNECTION, which this module is clean from
already.

Pick-to: 6.12
Change-Id: If5abdc89829ffa10891cb79d6af8536181dcfe74
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
commit85ea39b96b26a4fa6c9b410d1910633f8f3d2912
parentc11148feb8cbfb29fdf47ad40222fd56a6c16c6a
authorMarc Mutz <marc.mutz@qt.io>
committerMarc Mutz <marc.mutz@qt.io>
commit timeWed, 15 Jul 2026 12:43:24 +0000