Fix a debug statement. Only the callback function (performing the

incrementing of dpv_overall_oread) knows what its purpose is (and
often times it was bytes, not lines).

MFC after:	3 days
X-MFC-to:	stable/10

lib/libdpv/dpv.c

@@ -692,7 +692,7 @@ dpv(struct dpv_config *config, struct dpv_file_node *file_list)
 		if (!dpv_interrupt)
 			printf("\n");
 	} else
-		warnx("%s: %lli lines read", __func__, dpv_overall_read);
+		warnx("%s: %lli overall read", __func__, dpv_overall_read);
 
 	if (dpv_interrupt || dpv_abort)
 		return (-1);