atm: lanai: use %p to format kernel addresses instead of %x

Don't use %x and casting to print out a kernel address, instead use %p
and remove the casting.  Cleans up smatch warnings:

drivers/atm/lanai.c:1589 service_buffer_allocate() warn: argument 2 to
%08lX specifier is cast from pointer
drivers/atm/lanai.c:2221 lanai_dev_open() warn: argument 4 to %lx
specifier is cast from pointer

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>