This way the target will be created and have its properties
populated only one time.
I tried wrapping the whole file in an 'include guard', but that
broke the unit test in tests/auto/cmake/pass1 (and
the qt5_use_module function), because the function causes the
variables in the Config file to not exist outside of the
scope (eg for include directories), and yet, Qt5${Module}_FOUND is
still true even when the find_package was previously called in a
function, so it is not found and processed again.
The change in Qt5CoreConfigExtras.cmake does not need to be guarded
as it is only ever included from Qt5CoreConfig.
Change-Id: Iaa016563db5eb61294360ac9e003c9c923393d8c
Reviewed-by: Brad King <brad.king@kitware.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
77a03ebd8d