WIP: Fix bug allowing players to avoid falldamage (tiny MR)

I couldn't track down why this line was added because it came from the nexuiz repo and traditionally nobody bothered explaining why it's needed so here I am assuming it's not needed because it causes a bug.

To be honest, the falldamage code is kinda hacky since it only compares lengths of the vectors which means pressing jump still reduces the damage but at least that would be consistent - this bug only "works" sometimes.