Add missing #include <errno.h> line (for SunStudio Solaris).

This commit was SVN r19814.

orte/mca/iof/base/iof_base_output.c

@@ -30,6 +30,7 @@
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
+#include <errno.h>
 
 #include "orte/util/name_fns.h"
 #include "orte/runtime/orte_globals.h"