addons: mstpctl: check mstpctl-stp and bridge-stp and fix bridge cache update

addons: mstpctl: check mstpctl-stp and bridge-stp and fix bridge cache update

When an stp is enabled on an existing bridge mstpctl attributes are not always
configured by ifreload. This is due to a timing issue (cache) and some issue in
the mstpctl addon.

- Cache: when changing an existing bridge (done via netlink) we wait for the
kernel ack but we don't update our current cache with the new bridge attributes
This is bad because it means that the bridge cache data are stale until we
receive the notification from the kernel.

- Mstp addon: mstpctl-stp was deprecated in favor of bridge-stp, but in some
place, the mstpctl.py code checks for mstpctl-stp but not for bridge-stp. This
commit fixes the area related to this issue but this should be revisited in
a later commit

Ticket: CM-28951
Reviewed By: Roopa
Testing Done: precommit, smoke, evpn-smoke

Signed-off-by: Julien Fortin <julien@cumulusnetworks.com>