[pim] Fix dump byte type
diff --git a/pimd/pim_util.h b/pimd/pim_util.h
index 5863d5f..6f5bf22 100644
--- a/pimd/pim_util.h
+++ b/pimd/pim_util.h
@@ -38,6 +38,6 @@
 uint16_t pim_inet_checksum(const char *buf, int size);
 #endif /* PIM_USE_QUAGGA_INET_CHECKSUM */
 
-void pim_pkt_dump(const char *label, const char *buf, int size);
+void pim_pkt_dump(const char *label, const uint8_t *buf, int size);
 
 #endif /* PIM_UTIL_H */