FROMLIST: x86/mm: define ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT

Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT which turns on the
Speculative Page Fault handler when building for 64bit.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>

Link: https://lore.kernel.org/patchwork/patch/1062687/


Bug: 161210518
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I083e902d2daf671e3e06d10306dd9af591c9521b