fix shmem sysv build on solaris.

This commit was SVN r24806.

opal/mca/shmem/sysv/shmem_sysv_module.c

@@ -45,6 +45,9 @@
 #ifdef HAVE_STRING_H
 #include <string.h>
 #endif /* HAVE_STRING_H */
+#ifdef HAVE_NETDB_H
+#include <netdb.h>
+#endif /* HAVE_NETDB_H */
 
 #include "opal/constants.h"
 #include "opal_stdint.h"