[Development] Behavior change for QMake install targets since 5.9

[Oswald Buddenhagen]

On Fri, Jul 21, 2017 at 12:17:41PM +0000, Simon Hausmann wrote:
>    It's true that the internal install command does not support wild-cards.
>    We decided that it is the responsibility of the caller to resolve those
>    (qmake).
> 
we did? :}
as much as i despise wildcards in source file lists, this behavior is
actually documented for INSTALLS.
compare https://bugreports.qt.io/browse/QTCREATORBUG-17935
(on the upside, qmake is now consistent with qtc :D).