ehea: simplify conditional

Simplify: ((a && b) || (!a && !b)) => (a == b)

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Acked-by: Breno Leitao <leitao@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>