pmdinfogen: fix build on FreeBSD

error on compilation caused by missing include for libgen.h.
buildtools/pmdinfogen/pmdinfogen.c:402:4: error:
implicit declaration of function 'basename' is invalid in C99
                        basename(argv[0]));

Fixes: 840e5dfea3 ("pmdinfogen: fix usage message")

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

buildtools/pmdinfogen/pmdinfogen.c

@@ -15,6 +15,8 @@
 #include <limits.h>
 #include <stdbool.h>
 #include <errno.h>
+#include <libgen.h>
+
 #include <rte_common.h>
 #include "pmdinfogen.h"