ide-cd: Improve "weird block size" error message

Currently the error gets repeated too frequently, for example each
time HAL polls the device when a disc is present. Avoid that by using
printk_once instead of printk.

Also join the error and corrective action messages into a single line.

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>