Remove a bogus ast_free() that Kevin noticed. This was probably just left over

from pre-astobj2ified chan_sip.


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@155264 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -6426,7 +6426,6 @@ static struct sip_pvt *sip_alloc(ast_string_field callid, struct sockaddr_in *si
 
 	if (ast_string_field_init(p, 512)) {
 		ao2_t_ref(p, -1, "failed to string_field_init, drop p");
-		ast_free(p);
 		return NULL;
 	}