Carry over decomp documentation

[Dragorn421]

The way z64hdr copies headers from decomp means it doesn't include any documentation there is in source files.

For example in sys_math3d.c:

https://github.com/zeldaret/oot/blob/ed78d18a256ae941d2e821b14e17fb558703775d/src/code/sys_math3d.c#L148

/**
 * Creates a line between the intersections of two planes defined from `planeAA`x + `planeAB`y + `planeAC`z +
 * `planeADist` = 0 and `planeBA`x + `planeBB`y + `planeBC`z + `planeBDist` = 0, and outputs the line to `intersect`.
 * Returns false if the planes are parallel.
 */
s32 Math3D_PlaneVsPlaneNewLine(f32 planeAA, f32 planeAB, f32 planeAC, f32 planeADist, f32 planeBA, f32 planeBB,
                               f32 planeBC, f32 planeBDist, InfiniteLine* intersect) {

I'm not sure how one would go about automating that (definitely don't do it manually, right). I may try some day if nobody "fixed" it by then

EDIT: skawo is onto something https://github.com/skawo/Decomp2z64hdr (I hope he doesn't mind me linking it here)