rib: fix missing header includes

The standard integer types, and the size_t types are missing their
required header includes in the rib header file.

Fixes: 5a5793a5ffa2 ("rib: add RIB library")
Cc: stable@dpdk.org

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Vladimir Medvedkin <vladimir.medvedkin@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>

lib/librte_rib/rte_rib.h

@@ -18,6 +18,9 @@
  * Level compressed tree implementation for IPv4 Longest Prefix Match
  */
 
+#include <stdlib.h>
+#include <stdint.h>
+
 #include <rte_compat.h>
 
 #ifdef __cplusplus