net/smc: enable fallback for connection abort in state INIT

If a linkgroup is terminated abnormally already due to failing
LLC CONFIRM LINK or LLC ADD LINK, fallback to TCP is still possible.
In this case do not switch to state SMC_PEERABORTWAIT and do not set
sk_err.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>