Merge topic 'CMAKE_PROJECT_TOP_LEVEL_INCLUDES'

a6c34b0353 project(): Add new CMAKE_PROJECT_TOP_LEVEL_INCLUDES file injection point
8aa29a1793 CMakeDetermineSystem: Remove unreachable code

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !7250