Port headersclean check to CMake

Configure Qt with -DQT_FEATURE_headersclean=ON to enable the
check. There will be separate target for each module include
(e.g. QtCore_header_check), but the check will also be done
when the module is built for the first time.

There are notable differences to the qmake version:
- the build does not pick up anymore default defines or flags from
  the module, or Qt. Instead options like -fPIC they have to be listed
  explicitly. Also for this reason, we have to skip the vulkan-related
  headers from the check, since vulkan/vulkan.h is not necessarily
  in the compiler's default search path.
- some checks for nowadays unsupported compiler versions are
  removed.
- -Wdouble-promotion -Wshorten-64-to-32 is not added for clang
  builds; the qmake code path did never enforce that on CI
  machines (it was non-Apple clang only), and the check currently
  fails on these configurations.

Fixes: QTBUG-82615
Change-Id: I1cd303677b1472116910b6c27748f96436feb35e
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

0 files changed, 0 insertions, 0 deletions