Don't fail if can't create a socket to check master connection.

This happens for instance if ipv6 is disabled in the kernel but
/etc/hosts contains both ipv4 and ipv6 records for 'localhost'.

salt/utils/__init__.py

@@ -793,8 +793,8 @@ def dns_check(addr, port, safe=False, ipv6=None):
                 if h[0] != socket.AF_INET6 or ipv6 is not None:
                     candidates.append(candidate_addr)
 
-                s = socket.socket(h[0], socket.SOCK_STREAM)
                 try:
+                    s = socket.socket(h[0], socket.SOCK_STREAM)
                     s.connect((candidate_addr.strip('[]'), port))
                     s.close()