s390/cio: get rid of static console device

Remove the static console ccw device (and friends) and use dynamic
allocation for these structures. With this change the console
device is treated (mostly) like any other ccw device and we can
remove some special cases.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>