s390/mm: add p?d_folded() helper functions

Introduce and use p?d_folded() functions to clarify the page table
code a bit more.

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