ceph: remove redundant assignment to variable i

The variable i is being initialized with a value that is never read
and it is being updated later with a new value in a for-loop.  The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>