Add a missing header. Bleh.

This commit was SVN r23165.

orte/tools/orterun/orterun.c

@@ -53,6 +53,7 @@
 #include "opal/mca/paffinity/base/base.h"
 #include "opal/util/argv.h"
 #include "opal/util/output.h"
+#include "opal/util/opal_sos.h"
 #include "opal/util/basename.h"
 #include "opal/util/cmd_line.h"
 #include "opal/util/opal_environ.h"