net/smc: fix use of variable in cleared area

Do not use pend->idx as index for the arrays because its value is
located in the cleared area. Use the existing local variable instead.
Without this fix the wrong area might be cleared.

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