Resolves Iss1568 where LTO build gives warnings about unused variables

[LiamBrennan-UCSB]

I am updating ldmx-sw, here are the details.

What are the issues that this addresses?

This resolves #1568 by removing the unused variables in TrackDeDxMassEstimator.h, TrigScintFirmwareTracker.h, HcalDigiProducer.cxx, and adding override to TrkDeDxMassEstFeatures.h

Check List

• I successfully compiled ldmx-sw with my developments
• I ran my developments and the following shows that they are successful.

[LiamBrennan-UCSB]

@rodwyer100 Hey Rory, I was told to ping you as I deleted some variables I believe you added. They were causing the LTO build to fail. Did you need these variables? If so I can re-add them and use [[maybe_unused]] instead

[tvami]

/run-validation

[github-actions]

The validation workflow is running here: https://github.com/LDMX-Software/ldmx-sw/actions/runs/13254346603.

[tvami]

Looks good!

[tomeichlersmith]

Looks good to me too :)

[tvami]

Hey Rory, I was told to ping you as I deleted some variables I believe you added. They were causing the LTO build to fail. Did you need these variables? If so I can re-add them and use [[maybe_unused]] instead

I asked him on slack this is what he wrote

"I suppose they were used by earlier versions of firmware, especially the max depth variable as its hardcoded to be depth 2 now. The other variables (centroids) are only unused afaik because the last step (forming real tracks from the firmware ones) doesn't use those quantities. It calculates centroids from the cluster centroids. I believe its safe to remove them."