s390/uaccess: remove dead extern declarations, make functions static

Remove some dead uaccess extern declarations and also make some functions
static, since they are only used locally.

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