in retrospect, we were too conservative in 925fd32a2d making the
"feature" optional - it simply makes no sense to have qmake
automatically find the highest major (!) version of a library based on
a loosely defined platform-specific convention (not standard, unlike
ELF's .so versioning) with side effects.
Change-Id: Iba92df433b199a9fbff88358f6e0f6835f2e813d
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>