msvcrt: Rename _execve to MSVCRT__execve.

dlls/msvcrt/msvcrt.spec

@@ -211,7 +211,7 @@
 @ varargs _execlp(str str)
 @ varargs _execlpe(str str)
 @ cdecl _execv(str str)
-@ cdecl _execve(str str str)
+@ cdecl _execve(str str str) MSVCRT__execve
 @ cdecl _execvp(str str)
 @ cdecl _execvpe(str str str)
 @ cdecl _exit(long) MSVCRT__exit

dlls/msvcrt/process.c

@@ -295,7 +295,7 @@ MSVCRT_intptr_t CDECL _execv(const char* name, char* const* argv)
  * Like on Windows, this function does not handle arguments with spaces
  * or double-quotes.
  */
-MSVCRT_intptr_t CDECL _execve(const char* name, char* const* argv, const char* const* envv)
+MSVCRT_intptr_t CDECL MSVCRT__execve(const char* name, char* const* argv, const char* const* envv)
 {
   return _spawnve(MSVCRT__P_OVERLAY, name, (const char* const*) argv, envv);
 }