s390/mm: shorten addressing mode initialization

Shorten the code for addressing mode initialization. Also add missing
__init annotations, since this code is only used during kernel initialization.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
1 file changed