ANDROID: KVM: add pkvm_el2_mod_call_smccc() macro

This macro returns the whole arm_smccc_res object instead of res.a1, so
we can have up to 3 return values from a hypervisor call.

This patch is for an respin request.

Bug: 442763272
Bug: 433716010
Test: None

Change-Id: I5dc5e07c80eeb5c7b47df93b0ef13c627d6115fb
Signed-off-by: Kyriakos Ispoglou <ispo@google.com>
(cherry picked from commit 4581e739)