CMake: show Win32 and Generator_platform option values

Ensure key CMake option values are part of the CMake output to
facilitae user support when tool updates impact the wider CMake
actions, particularly ongoing 'improvements' in Visual Studio.

These CMake displays perform the same function as the build-options.txt
provided in the main Git for Windows. Cmake is already chatty.

Signed-off-by: Philip Oakley <[email protected]>

Author: PhilipOakley

contrib/buildsystems/CMakeLists.txt

@@ -67,6 +67,13 @@ endif()
 
 if(USE_VCPKG)
 	set(VCPKG_DIR "${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg")
+	message("WIN32: ${WIN32}") # show its underlying text values
+	message("VCPKG_DIR: ${VCPKG_DIR}")
+	message("VCPKG_ARCH: ${VCPKG_ARCH}") # maybe unset
+	message("MSVC: ${MSVC}")
+	message("CMAKE_GENERATOR: ${CMAKE_GENERATOR}")
+	message("CMAKE_CXX_COMPILER_ID: ${CMAKE_CXX_COMPILER_ID}")
+	message("CMAKE_GENERATOR_PLATFORM: ${CMAKE_GENERATOR_PLATFORM}")
 	if(NOT EXISTS ${VCPKG_DIR})
 		message("Initializing vcpkg and building the Git's dependencies (this will take a while...)")
 		execute_process(COMMAND ${CMAKE_SOURCE_DIR}/compat/vcbuild/vcpkg_install.bat ${VCPKG_ARCH})