[ping] Add top-level ping() function to ping a host

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/usr/pingmgmt.h

@@ -0,0 +1,16 @@
+#ifndef _USR_PINGMGMT_H
+#define _USR_PINGMGMT_H
+
+/** @file
+ *
+ * ICMP ping management
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+
+extern int ping ( const char *hostname, unsigned long timeout_ms, size_t len );
+
+#endif /* _USR_PINGMGMT_H */