af_iucv: get rid of compile warning

-Wunused-but-set-variable generates compile warnings. The affected
variables are removed.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>