KVM: PPC: e500: Mark "struct page" dirty in kvmppc_e500_shadow_map()

[ Upstream commit c9be85da ]

Mark the underlying page as dirty in kvmppc_e500_ref_setup()'s sole
caller, kvmppc_e500_shadow_map(), which will allow converting e500 to
__kvm_faultin_pfn() + kvm_release_faultin_page() without having to do
a weird dance between ref_setup() and shadow_map().

Opportunistically drop the redundant kvm_set_pfn_accessed(), as
shadow_map() puts the page via kvm_release_pfn_clean().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-53-seanjc@google.com>
Stable-dep-of: 87ecfdbc ("KVM: e500: always restore irqs")
Signed-off-by: Sasha Levin <sashal@kernel.org>