[netdrvr] ibmtr: PCMCIA IBMTR is ok on 64bit

For whatever value of 'OK' can be applied to the use of token ring. Seems
the 32bit to 64bit cleanups missed re-enabling the pcmcia driver

Closes #7133 and also reviewed the code in question

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>