[PATCH] s390: Fix missing release function and cosmetic changes

- Use kzalloc() in blacklist.c.
- Kill unwanted casts in blacklist.c.
- Provide release function for struct channel_subsystem.

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