Fix 9250 loop

[castlemccloud]

Previous refactoring of the code rolled both the assignment of the temp variable and the calibration matrix multiplication into a single loop.

This causes issue because every iteration of the loop for the matrix multiplication uses every value of temp, and it is not completely initialized until the final loop iteration.

The solution is to split the loop into two.

[kitlith]

Yep, this is:

• Unambiguously a bug (that is still present on main)
• Definitely my fault

I'll rebase it and apply a style tweak real quick.