netfilter: conntrack: remove uninitialized shadow variable

A recent commit introduced an unconditional use of an uninitialized
variable, as reported in this gcc warning:

net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_confirm':
net/netfilter/nf_conntrack_core.c:632:33: error: 'ctinfo' may be used uninitialized in this function [-Werror=maybe-uninitialized]
   bytes = atomic64_read(&counter[CTINFO2DIR(ctinfo)].bytes);
                                 ^
net/netfilter/nf_conntrack_core.c:628:26: note: 'ctinfo' was declared here
   enum ip_conntrack_info ctinfo;

The problem is that a local variable shadows the function parameter.
This removes the local variable, which looks like what Pablo originally
intended.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 71d8c47f ("netfilter: conntrack: introduce clash resolution on insertion race")
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>