Fall damage calculation should not take z-difference into account

Description:

On retail WoW, fall damage is computed only from the ratio between fall-time and fall-velocity. The difference in z-position values does not matter for the server. Here this is implemented wrong and damage is based on z-difference.

Current behaviour:

Expected behaviour:

Fall damage should be computed in the handler for MSG_MOVE_FALL_LAND and the damage should be proportional to the ratio between fall-time and fall-velocity in the packet. The difference in fall height should not matter for the damage.

Steps to reproduce the problem:

1. CHANGEME Step 1 include entries of affected creatures / items / quests with a link to the relevant wowhead page.
2. Step 2
3. Step 3

Branch(es):

CHANGEME 3.3.5, master or both

TC rev. hash/commit:

CHANGEME Copy the first line of the worldserver, authserver or bnetserver startup.
For example: TrinityCore rev. 0000000000 2000-01-09 11:31:41 +0100 (my branch) (Win64, RelWithDebInfo, Static) (bnetserver)

TDB version: CHANGEME Version of the TrinityCore database

Operating system: CHANGEME OS

Start by locating the C++ handler for MSG_MOVE_FALL_LAND and the current fall-damage calculation. Compare the existing inputs with the issue’s stated fall-time and fall-velocity rule; done means fall height or z-position difference no longer affects the resulting damage.