KVM: x86: Rename inject_pending_events() to kvm_check_and_inject_events()

Rename inject_pending_events() to kvm_check_and_inject_events() in order
to capture the fact that it handles more than just pending events, and to
(mostly) align with kvm_check_nested_events(), which omits the "inject"
for brevity.

Add a comment above kvm_check_and_inject_events() to provide a high-level
synopsis, and to document a virtualization hole (KVM erratum if you will)
that exists due to KVM not strictly tracking instruction boundaries with
respect to coincident instruction restarts and asynchronous events.

No functional change inteded.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220830231614.3580124-25-seanjc@google.com


Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>