s390/mm/ptdump: Generate address marker array dynamically

Generate the address marker array dynamically instead of modifying a large
static array at kernel startup. Each marker is added twice to the array:
with and without a "start" indicator. This way the code and logic stays
similar to other architectures.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>