mm/memory.c: fix race when faulting a device private page
    (CVE-2022-3523, bsc#1204363).
    nouveau: fix migrate_to_ram() for faulting page (CVE-2022-3523,
    bsc#1204363).
    mm/memory: return vm_fault_t result from migrate_to_ram()
    callback (CVE-2022-3523, bsc#1204363).
    kabi: workaround for migrate_vma.fault_page (CVE-2022-3523,
    bsc#1204363).