mm/PPC: prepare for killing free_all_bootmem_node()

Prepare for killing free_all_bootmem_node() by using free_all_bootmem().

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: "Suzuki K. Poulose" <suzuki@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>