powerpc/pseries: Added support for differentiated memory equivalent to ACPI special purpose memory (SPM) (SCM/pmem)

Bugzilla: http://bugzilla.redhat.com/1873825

Brew: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=45606610

Upstream Status: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/

Tested by Tarun Sahu Tarun.Sahu@ibm.com

Signed-off-by: gwalbon gwalbon@redhat.com