swiotlb: clean up reporting

commit 7d63fb3af87aa67aa7d24466e792f9d7c57d8e79 upstream.

This removes needless use of '%p', and refactors the printk calls to
use pr_*() helpers instead.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[bwh: Backported to 4.14:
 - Adjust filename
 - Remove "swiotlb: " prefix from an additional log message]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>