[PATCH] s390: common i/o layer

[PATCH] s390: common i/o layer

From: Cornelia Huck <cohuck@de.ibm.com>
From: Steffen Thoss <thoss@de.ibm.com>

common i/o layer changes:
 - Delay re-registration of a subchannel with a different subchannel id
   until the ccw device removal triggered from the subchannels remove
   function has completed.
 - Fix check when to call unreg_rereg.
 - Fix get_disc_cdev_by_devno.
 - Activate the time delay disablement facility. This saves a few cycles
   in millicode processing.
 - Don't ifdef reset of busy start time.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>