misc: Register a PPI for the vcpu stall detection virtual device

misc: Register a PPI for the vcpu stall detection virtual device

Request a PPI for each vCPU during probe which will be used by the host
to communicate a stall detected event on the vCPU. When the host raises
this interrupt from the virtual machine monitor, the guest is expected to
handle the interrupt and panic.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
Link: https://lore.kernel.org/r/20240703153732.3214238-3-sebastianene@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>