KVM: selftests: Convert the Hyper-V extended hypercalls test to printf asserts

Convert x86's Hyper-V extended hypercalls test to use printf-based
GUEST_ASSERT_EQ().

Link: https://lore.kernel.org/r/20230729003643.1053367-22-seanjc@google.com


Signed-off-by: Sean Christopherson <seanjc@google.com>