[BRIDGE] ebtables: fix allocation in net/bridge/netfilter/ebtables.c

Allocate an array of 'struct ebt_chainstack *', the current code allocates
array of 'struct ebt_chainstack'.

akpm: converted to use the

	foo = alloc(sizeof(*foo))

form.  Which would have prevented this from happening in the first place.

akpm: also removed unneeded typecast.

akpm: what on earth is this code doing anyway?  cpu_possible_map can be
sparse..

Signed-off-by: Jayachandran C. <c.jayachandran@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>