aha1542: remove loop from aha1542_outb

The loop in aha1542_outb with double-check is no longer needed, remove it.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>