LoongArch: KVM: Fix build due to API changes

Commit 8569992d ("KVM: Use gfn instead of hva for
mmu_notifier_retry") replaces mmu_invalidate_retry_hva() usage with
mmu_invalidate_retry_gfn() for X86, LoongArch also need similar changes
to fix build.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>