ANDROID: KVM: arm64: Generalize guest PA query

Soon, pvIOMMU would want to map pages from IOVA -> PA, using IPA,
so the hypervisor would need to query the PA for this pages and
possibly request to map them, this is very similar to the logic
used in device token requests.
So, reuse the code in a more generic way that is range friendly.

Bug: 357781595
Bug: 348382247
Bug: 236685427
Change-Id: Ic0235d97a9722b75c8583dc8550025fa796eda43
Signed-off-by: Mostafa Saleh <smostafa@google.com>