fix(FMA): LVR CLB not showing when preselected speed becomes active

[BravoMike99]

Fixes #[issue_no]

Summary of Changes

Hides "SPEED SEL" & "MACH SEL" FMA if autobrake max is selected.
Fixes possibility of ATHR messages being cleared on the FMA when preselected speed becomes active.

Screenshots (if necessary)

References

Video showing speed sel only appearing after autobrake max disarmed is now private sadly :(

Additional context

Discord username (if different from GitHub):
bruno_pt99

Testing instructions

Arm autobrake max and verify "BRK MAX" appears on the PFD.
Set the acceleration altitude to be the same as thrust reduction on the PERF TO page and insert a preselected speed on the PERF CLB page.
Perform a takeoff and verify that the "SPEED SEL" message appears after autobrake is disarmed (L/G up)
At reduction altitude, verify that LVR CLB appears on the FMA.

How to download the PR for QA

Every new commit to this PR will cause new A32NX and A380X artifacts to be created, built, and uploaded.

1. Make sure you are signed in to GitHub
2. Click on the Checks tab on the PR
3. On the left side, find and click on the PR Build tab
4. Click on either flybywire-aircraft-a320-neo or flybywire-aircraft-a380-842 download link at the bottom of the page

[LunakisDev]

Quality Assurance Trainee Report

Discord: LunakisLeaks
Object of testing: #8644
Tier of Testing: 1
Date: 22/5/2024

Testing Process:

1. Spawned at LGAV in C&D state
2. Started the aircraft
3. Set the acceleration altitude to be the same as the thrust reduction
4. Set the preselected speed
5. Performed a takeoff and verified that the "SPEED SEL" message appears after the autobrake is disarmed
6. Verified that "LVR CLB" appears on the FMA at the reduction altitude

Negatives:
N/A

Testing Results:
Passed

Conclusions:
LGTM