cmake: rename Windows detection cache file

To flatten the directory tree.

Closes #15859

.github/labeler.yml

@@ -516,7 +516,7 @@ Windows:
           - any-glob-to-all-files: "{\
               appveyor.*,\
               .github/workflows/windows.yml,\
-              CMake/Platforms/WindowsCache.cmake,\
+              CMake/win32-cache.cmake,\
               lib/*win32*,\
               lib/curl_multibyte.*,\
               lib/rename.*,\

CMakeLists.txt

@@ -525,9 +525,9 @@ include(CheckSymbolExists)
 include(CheckTypeSize)
 include(CheckCSourceCompiles)
 
-# Preload settings on Windows
 if(WIN32)
-  include("${CMAKE_CURRENT_SOURCE_DIR}/CMake/Platforms/WindowsCache.cmake")
+  # Preload settings on Windows
+  include("${CMAKE_CURRENT_SOURCE_DIR}/CMake/win32-cache.cmake")
 elseif(APPLE)
   # Fast-track predictable feature detections
   set(HAVE_EVENTFD 0)

Makefile.am

@@ -59,8 +59,8 @@ CMAKE_DIST =                                    \
  CMake/Macros.cmake                             \
  CMake/OtherTests.cmake                         \
  CMake/PickyWarnings.cmake                      \
- CMake/Platforms/WindowsCache.cmake             \
  CMake/Utilities.cmake                          \
+ CMake/win32-cache.cmake                        \
  CMakeLists.txt
 
 VC_DIST = projects/README.md                           \