Qt5Config restricts search paths of Qt components to ${_qt5_install_prefix}
to prevent accidentally using system Qt modules in case of restricted Qt
configuration. However this does not work properly when Qt is used without
installation, in particular when building cmake-based QtWebKit as a Qt
submodule, because ${_qt5_install_prefix} resolves to QtBase and does not
contain components from other modules.
This patch changes search path from ${_qt5_install_prefix} to all qt5
subdirectories.
Change-Id: Icf01a256097710889573ad69d847b9c3bffa1449
Reviewed-by: Kevin Funk <kevin.funk@kdab.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
