Add #include of sys/types.h for .c files that include missing.h to

be sure that size_t and ssize_t are defined.

src/error.c

@@ -14,12 +14,15 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <config.h>
+
+#include <sys/types.h>
+
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
-#include <config.h>
 #include <missing.h>
 #include "error.h"