Fix errors found by Coverity Static Analysis.

Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>

clock.c

@@ -401,7 +401,7 @@ struct clock *clock_create(int phc_index, struct interface *iface, int count,
 			   enum timestamp_type timestamping, struct defaultDS *ds,
 			   enum servo_type servo)
 {
-	int i, fadj = 0, max_adj, sw_ts = timestamping == TS_SOFTWARE ? 1 : 0;
+	int i, fadj = 0, max_adj = 0.0, sw_ts = timestamping == TS_SOFTWARE ? 1 : 0;
 	struct clock *c = &the_clock;
 	char phc[32];
 	struct interface udsif;

config.c

@@ -341,6 +341,9 @@ int config_read(char *name, struct config *cfg)
 					continue;
 				}
 				current_port = config_create_interface(port, cfg);
+				if (current_port < 0) {
+					return -1;
+				}
 			}
 			continue;
 		}

port.c

@@ -1678,6 +1678,7 @@ struct port *port_open(int phc_index,
 		pr_err("port %d: PHC device mismatch", number);
 		pr_err("port %d: /dev/ptp%d requested, but /dev/ptp%d attached",
 		       number, phc_index, checked_phc_index);
+		free(p);
 		return NULL;
 	}