ANDROID: KVM: Send VM availability FF-A direct messages to Trustzone

Store the secure partitions interested in receiving VM availability
messages in an array when the caller invokes the
FFA_PARTITIONS_INFO_GET interface.
Notify these secure partitions about VM creation and teardown
and keep track whether a VM creation message has been sent
successfully from pKVM to the TEE.

If we get a later destruction message for the same VM,
make sure to complete the creation message first before sending
out the destruction one. The FF-A spec only allows destruction
messages for VMs in the available state, and SPs should return
INVALID_PARAMETERS when receiving this message in any other state.

Bug: 269285339
Bug: 278749606
Change-Id: Ic812ad8b6fb3f30c821085141900c4e22555af57
Signed-off-by: Sebastian Ene <sebastianene@google.com>
Signed-off-by: Andrei Homescu <ahomescu@google.com>