[pim] Fix net/host byte order
diff --git a/pimd/pim_assert.h b/pimd/pim_assert.h
index 6a8594c..feeb91d 100644
--- a/pimd/pim_assert.h
+++ b/pimd/pim_assert.h
@@ -58,7 +58,7 @@
 int pim_assert_metric_match(const struct pim_assert_metric *m1,
 			    const struct pim_assert_metric *m2);
 
-int pim_assert_build_msg(char *pim_msg, int buf_size,
+int pim_assert_build_msg(uint8_t *pim_msg, int buf_size,
 			 struct interface *ifp,
 			 struct in_addr group_addr,
 			 struct in_addr source_addr,