Fix use-after-free bug in __dns_lookup

If the type of the first answer does not match with the requested type,
then the dotted name was freed. If there are no further answers in
the DNS reply, this pointer was used later on in the same function.
Additionally it is passed to the caller, and caused strange
behaviour.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

libc/inet/resolv.c

@@ -1517,10 +1517,8 @@ int attribute_hidden __dns_lookup(const char *name,
 				memcpy(a, &ma, sizeof(ma));
 				if (a->atype != T_SIG && (NULL == a->buf || (type != T_A && type != T_AAAA)))
 					break;
-				if (a->atype != type) {
-					free(a->dotted);
+				if (a->atype != type)
 					continue;
-				}
 				a->add_count = h.ancount - j - 1;
 				if ((a->rdlength + sizeof(struct in_addr*)) * a->add_count > a->buflen)
 					break;