qed: do not use unitialized variable

Do not write random bytes from the kernel stack when
calling qed_wr.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>