Awayviewmobj sanity checks

This fixes the P_CameraCheckWater crash encountered in Acidic Alpines in Kimokawaiii, and possibly a few similar scenarios. Turns out that Acidic Alpines uses a MT_THOK awayviewmobj for some reason, which eventually is removed from the map (leading to the crash).

The problem is really just that the game never really considered an alt view cam mobj that gets removed when in use. =P

changed the description

I have already experienced a few SIGSEV crashes with the map but I didn't bother to report them... I hope this patch fixes it.

Lach confirmed this as fixed for Acidic Alpines, so +1

Steel also confirmed this as fixed for Subarashii's isometric cam, attached. This one doesn't work for me, will investigate. Doesn't block the +1 (as MPC said, separate fix.)

isometric.wad

@digiku Wrong. Steel Titanium meant my fix. https://github.com/STJr/SRB2/pull/367

Yeah, this MR only fixes the Acidic Alpines crash

and yes, that separate fix also fixes the isometric cam.

merged

mentioned in commit ab7f0ca4

mentioned in issue #38 (closed)