Fix *_temp_file(): argument to close(2) cannot be negative.

  *** CID 1198149:  Argument cannot be negative  (NEGATIVE_RETURNS)
  /src/path/temp.c: 258 in create_temp_file()
  257             fd = mkstemp(name);

  >>>     CID 1198149:  Argument cannot be negative  (NEGATIVE_RETURNS)
  >>>     "fd" is passed to a parameter that cannot be negative.

  258             close(fd);
  259             if (fd < 0) {

  *** CID 1198148:  Argument cannot be negative  (NEGATIVE_RETURNS)
  283        fd = mkstemp(name);
  284        if (fd < 0)
  285                goto error;

  [...]

  295     error:

  >>>     CID 1198148:  Argument cannot be negative  (NEGATIVE_RETURNS)
  >>>     "fd" is passed to a parameter that cannot be negative.

  296             close(fd);