rose: use %*ph specifier

Instead of dereference each byte let's use %*ph specifier in the printk()
calls.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>