Update in sysinv to use stevedore dynamically load the helm
plugins instead of listing them statically in helm code.
Tested on AIO-SX:
- fresh install + config_controller with kubernetes
- stx-openstack application installed successfully through
"system application-apply" command.
- all pods are running after the subsequent lock/unlock
Change-Id: I4efba886b796bda87984d3fd8838478ce7a8f1bf
Story: 2003909
Task: 28187
Signed-off-by: Angie Wang <angie.wang@windriver.com>