serial: jsm: Convert jsm_printk to jsm_dbg

These printks should all be emitted at KERN_DEBUG level.
Make them dependent on CONFIG_DEBUG or (#define DEBUG)
simplify the code a bit.

Add missing newlines where appropriate.

Most all of these messages could be deleted too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>