🩹 Fix LINEAR_ADVANCE/LIN_ADVANCE typo

[vovodroid]

Fix usage of wrong LINEAR_ADVANCE define, it's LIN_ADVANCE in all Marlin code.

[ellensp]

The associated error message doesn't quite make sense. (I know you didn't change this, it was changed in 23e2cb0)

The original error was #error "LINEAR_ADVANCE currently requires NUM_AXES <= 3." which makes a lot more sense than "LIN_ADVANCE does not currently support the inclusion of an I axis."

The test for HAS_I_AXIS seems to have been used just to see if NUM_AXES is > 3. I being the 4th axis

Perhaps this could be updated to be clearer with the following

#elif ENABLED(LIN_ADVANCE) && NUM_AXES > XYZ
  #error "LIN_ADVANCE currently requires NUM_AXES <= 3."

But this raises the question why? From what I know (and I'm not a expert in LIN_ADVANCE) it only effects the E axis,
Ie it is rapid forward and back moves on E to reduce nozzle pressure... So why would that care if there a 3 or 9 axis?

@DerAndere1 Could you comment here? Since you added this check back in #23112

[DerAndere1]

The problem is that I dit not extened the LIN_ADVANCE code in function planner._poulate_block to more axes. The offending section starts here:

Marlin/Marlin/src/module/planner.cpp

Line 2480 in e7c9cf3

float e_D_ratio = (target_float.e - position_float.e) /

I do not know what the code should do (are calculations supposed to be done in cartesian space or in joints-space AKA stepper space? i.e. do we look for distances along axes in a cartesian space or are the steps of each joint/motor relevant?) As long as this is unclear, the fix of the sanity check as proposed in this PR looks good to me.