[ATM]: ENI155P error handling fix

From: Panagiotis Issaris <takis@lumumba.luc.ac.be>

In the ENI155P device driver in six possible failure cases the requested
irq is not being released.

In three of the above possible failure cases additionally there seems to
be a memory leak.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>