CMake: Decouple cmake utility functions from top-level CMakeLists.txt

Problem:
- These utility functions are only used in `AK`, but are being defined
  in the top-level. This clutters the top-level.

Solution:
- Move the utility functions to `Meta/CMake/utils.cmake` and include
  where needed.
- Also, move `all_the_debug_macros.cmake` into `Meta/CMake` directory
  to consolidate the location of `*.cmake` script files.

AK/CMakeLists.txt

@@ -1,2 +1,3 @@
+include(${CMAKE_SOURCE_DIR}/Meta/CMake/utils.cmake)
 serenity_install_headers(AK)
 serenity_install_sources(AK)