AP_RangeFinder: investigate and resolve RPLidar startup issue

This reports comes from this discussion in the Rover-4.0 category: https://discuss.ardupilot.org/t/bad-lidar-health-message-with-rplidar-a2m8/52350

At least 3 users have reported that the RPLidar must be powered up before the flight controller or "Bad Lidar Health" messages appear on the HUD.

We should investigate and then try to resolve this issue. Perhaps there are some startup messages sent by the driver that we should keep resending until we start receiving distances

Start with the AP_RangeFinder RPLidar driver and the linked Rover-4.0 discussion, then reproduce the startup-order difference by powering the RPLidar before and after the flight controller. Done means the driver starts reliably in either order, receives distances, and no longer produces the reported Bad Lidar Health HUD message.

Written by the indexing model from the issue text.