accel/mshv: write synthetic MSRs after migration

Write partition-wide synthetic MSRs. This ensures the hypercall page and
SynIC facilities are set up before vCPUs attempt to use it.

Signed-off-by: Magnus Kulke <magnuskulke@linux.microsoft.com>
Link: https://lore.kernel.org/r/20260710101534.664604-10-magnuskulke@linux.microsoft.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 files changed