[Development] 5.7.0-rc compile error

[Tim Blechmann]

hi all,

compiling 5.7.0-rc (sometimes) fails with the following error when
building qt as static library:

> error	15-Jun-2016 20:04:06	make[4]: *** No rule to make target `/Volumes/build/bamboo-build/THIRDP-QT9-BUILDMAC/build-Qt-5.7.0-rc-macx-clang-static/qt3d/lib/libQt53DQuick_debug.a', needed by `../../../../qml/Qt3D/Extras/libquick3dextrasplugin_debug.a'.  Stop.
> error	15-Jun-2016 20:04:06	make[3]: *** [debug-all] Error 2
> error	15-Jun-2016 20:04:06	make[2]: *** [sub-quick3d-imports-extras-make_first] Error 2

probably an missing dependency for parallel builds as it doesn't happen
all the time ... would be nice if this could be fixed before 5.7.0 comes
out.

thanks a lot,
tim