Fix MinGW/Native Windows link for PostreSQL documentation
Fix MinGW/Native Windows link for PostreSQL documentation

The sql-driver.qdoc referencing to the title will be updated in a soon
to follow patch for qtbase documentation.

Change-Id: I18179ca949e7e8fd527a707abe0735241d999089
Reviewed-by: Casper van Donderen <808524cef5c654648bea2a2b954f3b3445ed083c@nokia.com>

kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc