Fix cast on WAL lag computation to (long long)

HISTORY

@@ -21,3 +21,4 @@
                  Correct freeing of memory from first_wal_segment (Daniel)
                  Allow creating recovery.conf file with a password (Daniel)
                  Inform when STANDBY CLONE sees an unused config file (Daniel)
+                 Use 64-bit computation for WAL apply_lag (Greg)

repmgrd.c

@@ -450,7 +450,7 @@ walLocationToBytes(char *wal_location)
 		log_err("wrong log location format: %s\n", wal_location);
 		return 0;
 	}
-	return ((xlogid * 16 * 1024 * 1024 * 255) + xrecoff);
+	return (( (long long) xlogid * 16 * 1024 * 1024 * 255) + xrecoff);
 }