Add support for ARM64 architecture so that the driver can now be built
and VMCI device can be used.

Update Kconfig file to allow the driver to be built on ARM64 as well.
Fail vmci_guest_probe_device() on ARM64 if the device does not support
MMIO register access.  Lastly, add virtualization specific barriers
which map to actual memory barrier instructions on ARM64, because it
is required in case of ARM64 for queuepair (de)queuing.
Reviewed-by: Bryan Tan <bryantan@vmware.com>
Reviewed-by: Cyprien Laplace <claplace@vmware.com>
Signed-off-by: Vishnu Dasa <vdasa@vmware.com>
Link: https://lore.kernel.org/r/20220414193316.14356-1-vdasa@vmware.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>