CMake: Add facility to mark package dependencies as optional

Every public dependency of a Qt module results in a find_package call in
the consuming project. But not all public dependencies are mandatory.

For example, vulkan is only needed if the user project actually uses Qt
classes that pull in vulkan headers.

This patch adds the option MARK_OPTIONAL to qt_find_package.
Dependencies that are marked as optional will not produce an error on
find failure.

Task-number: QTBUG-86421
Change-Id: Ia767e7f36991e236582c7509cbd37ea3487bb695
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

0 files changed, 0 insertions, 0 deletions