In fetch_resolve(), if the port number or service name is included in

the host argument (e.g. "www.freebsd.org:443"), the service pointer,
which is supposed to point to the port or service part, instead points
to the separator, causing getaddrinfo() to fail.

Note that I have not been able to trigger this bug with fetch(1), nor
do I believe it is possible, as libfetch always parses the host:port
specification itself.  I discovered it when I copied fetch_resolve()
into an unrelated project.

MFC after:	3 days

lib/libfetch/common.c

@@ -291,7 +291,7 @@ fetch_resolve(const char *addr, int port, int af)
 			goto syserr;
 		service = sbuf;
 	} else if (*sep != '\0') {
-		service = sep;
+		service = sep + 1;
 	} else {
 		service = NULL;
 	}