Revert "ping: fix ping6 name resolution for hostnames with link-local…

… addresses"

This reverts commit d217170.

Reverting it allows pinging IPv4-mapped IPv6 address because glibc...

fe80::fc54:ff:fe29:5693%vnet0

Pinging IPv6 link scope address without scope ID still works:
$ ./builddir/ping/ping -v -c1 fe80::fc54:ff:fe29:5693
./builddir/ping/ping: sock4.fd: 3 (socktype: SOCK_RAW), sock6.fd: 4 (socktype: SOCK_RAW), hints.ai_family: AF_UNSPEC

ai->ai_family: AF_INET6, ai->ai_canonname: 'fe80::fc54:ff:fe29:5693'
PING fe80::fc54:ff:fe29:5693 (fe80::fc54:ff:fe29:5693) 56 data bytes
64 bytes from fe80::fc54:ff:fe29:5693%vnet0: icmp_seq=1 ident=53558 ttl=64 time=0.066 ms

--- fe80::fc54:ff:fe29:5693 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.066/0.066/0.066/0.000 ms

Therefore there is no reason to force

Original effort from issue iputils#252 [1] (PR#253 [2])
[1] iputils#252
[2] iputils#253

ping/ping.c

@@ -677,14 +677,6 @@ main(int argc, char **argv)
 	if (rts.tclass)
 		set_socket_option(&sock6, IPPROTO_IPV6, IPV6_TCLASS, &rts.tclass, sizeof(rts.tclass));
 
-	/* getaddrinfo fails to indicate a scopeid when not used in dual-stack mode.
-	 * Work around by always using dual-stack name resolution.
-	 *
-	 * https://github.com/iputils/iputils/issues/252
-	 */
-	int target_ai_family = hints.ai_family;
-	hints.ai_family = AF_UNSPEC;
-
 	if (!strchr(target, '%') && sock6.socktype == SOCK_DGRAM &&
 		inet_pton(AF_INET6, target, buf) > 0 &&
 		(IN6_IS_ADDR_LINKLOCAL(buf) || IN6_IS_ADDR_MC_LINKLOCAL(buf))) {
@@ -703,8 +695,8 @@ main(int argc, char **argv)
 				   str_family(ai->ai_family),
 				   ai->ai_canonname ? ai->ai_canonname : "");
 
-		if (target_ai_family != AF_UNSPEC &&
-			target_ai_family != ai->ai_family) {
+		if (hints.ai_family != AF_UNSPEC &&
+			hints.ai_family != ai->ai_family) {
 			if (!ai->ai_next) {
 				/* An address was found, but not of the family we really want.
 				 * Throw the appropriate gai error.