winrt: Enable windeployqt by default for Visual Studio projects

Using Visual Studio a user very seldom wants to disable the automatic
invocation of windeployqt. Hence switch from opt-in behavior to opt-out.

This also fixes first user experience to invoke qmake –tp vc and then
hit run on examples.

[ChangeLog][Platform Specific Changes][qmake] qmake-generated Visual
Studio projects now automatically invoke windeployqt by default.

Task-number: QTBUG-52008
Change-Id: Iee1607269c38c7f6c726f554978ac05477bebe5e
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>