linux: add VMADDR_CID_LOCAL

In Linux we replaced VMADDR_CID_RESERVED with VMADDR_CID_LOCAL
in commit ef343b35d46667668a099655fca4a5b2e43a5dfe.
It is available since Linux v5.6, and it can be used to do
local communication if supported.

This patch deprecates VMADDR_CID_RESERVED for backward
compatibility.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>