Fix OOB in missiles.cpp

MFILE_NONE does not correspond to the last item of misfiledata array and
is actually greater than the length of that array causing out-of-bounds
crash on iOS (reproduced when applying rogue's Disarm Trap skill).

Source/missiles.cpp

@@ -1067,6 +1067,10 @@ void SetMissAnim(int mi, int animtype)
 {
 	int dir = missile[mi]._mimfnum;
 
+    if (animtype > MFILE_NULL) {
+        animtype = MFILE_NULL;
+    }
+
 	missile[mi]._miAnimType = animtype;
 	missile[mi]._miAnimFlags = misfiledata[animtype].mFlags;
 	missile[mi]._miAnimData = misfiledata[animtype].mAnimData[dir];