[Qt5-compat] Change Q_WS_* macroses to Q_OS_*

[naihil]

Q_WS_* macros removed from Qt5, to determine platform use Q_OS_* macros which exists in Qt4 and Qt5

[dakcarto]

@m-kuhn This appears to be necessary (thank you @naihil). Seems to be missing the changes for the new internal qwtpolar though. Should those edits be added?

[naihil]

One more thing:
In multiple places Q_WS_X11 macro used, which removed from qt5 too. And there is no simple way to determine window server (X/Wayland), but i dont have linux box with qt5 now, may be wrong.

[m-kuhn]

@naihil Thank you.
X11/Wayland seems not to be a compile-time but a run-time switch (see http://lists.qt-project.org/pipermail/interest/2013-June/007548.html )
Q_OS_UNIX can be used there, which will trigger for Linux/X11 builds. If problems surface once people start running Wayland we can still react. Actually it's the Q_WS_X11 macro is not used much.

I assume this does not break any Qt4 builds from what I have read?

Internal qwtpolar does not work with Qt5 anyway and needs to be built externally, so I don't think it makes sense to change anything there.

[naihil]

Ok, changed all Q_WS_* macroses, except those in qwtpolar.

I dont try to build with internal qwtpolar, external qwtpolar-1.1.1 builds fine with Qt5

[m-kuhn]

Thank you @naihil