patch 9.1.1842: MS-Windows: build failure when mzscheme is included

Problem:  MS-Windows: build failure when mzscheme is included
          (dertuxmalwieder, after v9.1.1838)
Solution: skip specific section when PROTO is defined
          (Hirohito Higashi)

fixes: #18529
closes: #18530

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

Author: h-east

src/if_mzsch.c

@@ -485,14 +485,16 @@ static void (*dll_scheme_set_config_path)(Scheme_Object *p);
 #  define scheme_set_config_path dll_scheme_set_config_path
 # endif
 
-# if MZSCHEME_VERSION_MAJOR >= 500
-#  if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || defined(IMPLEMENT_THREAD_LOCAL_EXTERNALLY_VIA_PROC)
+# ifndef PROTO
+#  if MZSCHEME_VERSION_MAJOR >= 500
+#   if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || defined(IMPLEMENT_THREAD_LOCAL_EXTERNALLY_VIA_PROC)
 // define as function for macro in schthread.h
 Thread_Local_Variables *
 scheme_external_get_thread_local_variables(void)
 {
     return dll_scheme_external_get_thread_local_variables();
 }
+#   endif
 #  endif
 # endif
 

src/proto/if_mzsch.pro

@@ -1,5 +1,4 @@
 /* if_mzsch.c */
-Thread_Local_Variables *scheme_external_get_thread_local_variables(void);
 int mzscheme_enabled(int verbose);
 void mzvim_check_threads(void);
 char *did_set_mzquantum(optset_T *args);

src/version.c

@@ -729,6 +729,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1842,
 /**/
     1841,
 /**/