s390: remove cu3088 layer for lcs and ctcm

The cu3088-driver used as common base for lcs- and ctcm-devices
makes it difficult to assign the appropriate driver to an lcs-device
or a ctcm-device. This patch eliminates the cu3088-driver and thus
the root device "cu3088". Path /sys/devices/cu3088 is replaced with
the pathes /sys/devices/lcs and /sys/devices/ctcm.

Patch is based on a proposal from Cornelia Huck.

Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>