This patch adds the config option 'live_migration_scheme = tls' to the
secure live migration guide.
To let the live migration use the qemu native tls, some configuration of
the compute nodes is needed. The guide describes this but misses the
'live_migration_scheme' config option.
It is necessary to set 'live_migration_scheme' to tls to use the
connection uri for encrypted traffic. Without this parameter everything
seems to work, but the unencrypted tcp-connection is still used for the
live migration.
Closes-Bug: #1919357
Change-Id: Ia5130d411706bf7e1c983156158011a3bc6d5cd6
(cherry picked from commit 5d5ff82bab)
(cherry picked from commit 276b8db5af)
(cherry picked from commit a968289b1f)
(cherry picked from commit 8559ceeec4)