[Development] Dropping sqlite2 plugin for Qt6/cmake port

[Albert Astals Cid]

While trying to get more src/plugins/sqldrivers/ code built with CMake i 
realized that there is no FindSQLite2.cmake in cmake and we would have to 
create/maintain our own.

Then i realized that the latest release of sqlite2 was on 2005 and thought 
maybe we can just drop it?

So I'm proposing to drop src/plugins/sqldrivers/sqlite2/ from Qt6/cmake port 
of Qt.

Opinions?

Best Regards,
  Albert

P.S: sqlite3 code is already building fine in the cmake port

-- 
Albert Astals Cid | albert.astals.cid at kdab.com | Software Engineer
Klarälvdalens Datakonsult AB, a KDAB Group company
Tel: Sweden (HQ) +46-563-540090, USA +1-866-777-KDAB(5322)
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