haven: rm: Add HH_SELF_VM name

RM accepts "VMID 0" as meaning "self." Thus, add a vm_name "HH_SELF_VM"
which means the same. Haven RM console operates on vm_names and can use
HH_SELF_VM to talk to RM about this VM's console.

Change-Id: I7663db28497ad86a94d4a8c98f3b7068f5644915
Signed-off-by: Elliot Berman <eberman@codeaurora.org>