RTL: Add approaches for rtl to home and rally points

[KonradRudin]

Solved Problem

When a VTOL performs a RTL to the home or rally position, it flies straight to the designated position and lands there. If it is too high, it will circle around the designated position. however, it is desired to actually define a landing pattern with a designated loiter position when performing a RTL for a vtol in Fixed wing mode.

Fixes #{Github issue ID}

Solution

• Using the MAVLINK Safe point messages, we can not only upload safe point landing locations, but designated loiter positions as well. Multiple loiter points can be defined for the safe point. The storage order of the loiter points determine to which safe landing position the loiter point belongs to.
• Update the RTL logic to check if there exists some loiter position for the rtl landing point. If it exists, choose the best approach best on current vehicle location and wind condition and the perform a mission landing approach.

Test coverage

• Unit/integration test: tested in SITL with standard_vtol
• Simulation/hardware testing logs:
  • https://logs.px4.io/plot_app?log=7db47a76-72a2-417e-a9ac-70ff1f6f1794
  • https://logs.px4.io/plot_app?log=fd874a72-2c96-40e1-bd49-71695687dbd8

Context

Related links, screenshot before/after, video

[KonradRudin]

I put 2a5c60c and b898bf3 in a separate PR here since those are fixes not related to the rtl home approaches

[KonradRudin]

rebased on main and squashed commits

[KonradRudin]

Added flight logs in the description