Make cmake.h available everywhere.

The definition of HAVE_CMAKE_H is now at the very top of the main
CMakeLists.txt, so that it applies to all objects. And the consequent
include of cmake.h is at the very top of defs.h, so that it should be
included first by everything. This way, I don't have to worry any more
that the HAVE_FOO definitions in cmake.h might accidentally have
failed to reach some part of the code.

CMakeLists.txt

@@ -3,6 +3,8 @@ project(putty LANGUAGES C)
 
 include(cmake/setup.cmake)
 
+add_compile_definitions(HAVE_CMAKE_H)
+
 add_library(utils STATIC
   utils/base64_decode_atom.c
   utils/base64_encode_atom.c
@@ -161,8 +163,6 @@ add_executable(test_wildcard
 target_compile_definitions(test_wildcard PRIVATE TEST)
 target_link_libraries(test_wildcard utils ${platform_libraries})
 
-add_compile_definitions(HAVE_CMAKE_H)
-
 foreach(subdir ${PLATFORM_SUBDIRS})
   add_subdirectory(${subdir})
 endforeach()

defs.h

@@ -22,6 +22,10 @@
 #error Do not compile this code base with NDEBUG defined!
 #endif
 
+#if HAVE_CMAKE_H
+#include "cmake.h"
+#endif
+
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>                     /* for __MINGW_PRINTF_FORMAT */

unix/platform.h

@@ -5,10 +5,6 @@
 #ifndef PUTTY_UNIX_PLATFORM_H
 #define PUTTY_UNIX_PLATFORM_H
 
-#if HAVE_CMAKE_H
-#include "cmake.h"
-#endif
-
 #include <stdio.h>                     /* for FILENAME_MAX */
 #include <stdint.h>                    /* C99 int types */
 #ifndef NO_LIBDL

windows/platform.h

@@ -5,10 +5,6 @@
 #ifndef PUTTY_WINDOWS_PLATFORM_H
 #define PUTTY_WINDOWS_PLATFORM_H
 
-#if HAVE_CMAKE_H
-#include "cmake.h"
-#endif
-
 #include <winsock2.h>
 #include <windows.h>
 #include <stdio.h>                     /* for FILENAME_MAX */