Netmiko's `ssh_dispatcher` calculates platform lists at module import
time. When custom device types (like Huawei CE) are registered
dynamically, these cached lists become stale and do not include the
new platforms.
This change imports `netmiko.ssh_dispatcher` and recalculates the
`platforms`, `platforms_base`, and `telnet_platforms` attributes to
ensure Netmiko recognizes the custom device types.
44f802ae4f