follow-up: MSYS2 build fix

include/windconf.h

@@ -108,7 +108,6 @@ extern char *windows_exepath(void);
  */
 
 #ifdef __GNUC__
-#include <process.h>
 #define MD_USE_TMPFILE_S
 #
 #ifdef strncasecmp
@@ -164,7 +163,7 @@ typedef SSIZE_T ssize_t;
 #endif /* _MSC_VER */
 
 /* The following is needed for prototypes of certain functions */
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) || defined(__GNUC__)
 #include <process.h> /* Provides prototypes of exit(), spawn()      */
 #endif