Fix use of incorrect method when resolving CNAMES

[jeteon]

When checking CNAME records, the code calls:

self.resolver.query(cname_host, "A", total_rechecks)

Which results in an integer argument being given for the name_server argument in the resolver.query method which has the signature:

def query(self, hostname, query_type = 'ANY', name_server = False, use_tcp = False):

And causes an error to be raised in dnslib:

File "dnslib/dns.py", line 375, in send
    sock.sendto(self.pack(),(dest,port))
TypeError: coercing to Unicode: need string or buffer, int found

It seems from the call signature intended to be recursive call to the check method itself with a preservation of the retry count so that's what I put in.