atm: fore200e: use %pK to format kernel addresses instead of %x

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

drivers/atm/fore200e.c:3093 fore200e_proc_read() warn: argument 3 to %08x
specifier is cast from pointer

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