am53c974: remove left-over debugging code

A shost_printk() statement was left over from debugging.
It can safely be removed; the same information is displayed
in the debugging message some lines further down.

Cc: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>