[SCTP]: Correctly initialize error when parameter validation failed.

When parameter validation fails, there should be error causes that
specify what type of failure we've encountered.  If the causes are not
there, we lacked memory to allocated them.  Thus make that the default
value for the error.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>