hw/arm/virt: Extend nested and mte checks to hvf

hw/arm/virt: Extend nested and mte checks to hvf

The virt machine has properties to enable MTE and Nested Virtualization
support. However, its check to ensure the backing accel implementation
supports it today only looks for KVM and bails out if it finds it.

Extend the checks to HVF as well as it does not support either today.
This will cause QEMU to print a useful error message rather than
silently ignoring the attempt by the user to enable either MTE or
the Virtualization extensions.

Reported-by: saar amar <saaramar5@gmail.com>
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Message-id: 20211123122859.22452-1-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>