[SRU][linux-aws v5.4 kernels] add pvtime support for arm64 guests

[Kamal Mostafa]

BugLink: https://bugs.launchpad.net/bugs/1889282

The mainline patch set "arm64: Stolen time support" and its prerequisites are
required to support future AWS instance types.

Almost all clean mainline cherry-picks (one trivial backport).

Internal AWS testing yields positive test results for aws/focal and
aws-5.4/bionic test kernels.

Pull reqs for aws/focal and aws-5.4/bionic (identical commits) follow.

 -Kamal

-----

Christoffer Dall (1):
      KVM: arm/arm64: Factor out hypercall handling from PSCI code

Mark Rutland (5):
      arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()
      arm64: errata: use arm_smccc_1_1_get_conduit()
      arm: spectre-v2: use arm_smccc_1_1_get_conduit()
      firmware/psci: use common SMCCC_CONDUIT_*
      firmware: arm_sdei: use common SMCCC_CONDUIT_*

Steven Price (9):
      KVM: arm64: Document PV-time interface
      KVM: arm64: Implement PV_TIME_FEATURES call
      KVM: Implement kvm_put_guest()
      KVM: arm64: Support stolen time reporting via shared structure
      KVM: Allow kvm_device_ops to be const
      KVM: arm64: Provide VCPU attributes for stolen time
      arm/arm64: Provide a wrapper for SMCCC 1.1 calls
      arm/arm64: Make use of the SMCCC 1.1 wrapper
      arm64: Retrieve stolen time as paravirtualized guest