Blender Git Loki

Smoke viewport: remove dead code.

OCD commit, but cleans the code a bit:
- the first `if 0` block was supposed to draw collision objects but is
vastly outdated as most of the SmokeCollisionSettings member variables
were removed a few years ago and collision objects are drawn like other
objects anyway. Also it was committed already commented out back in
2009.
- the second `if 0` block was doing pretty much the same thing as the
few lines above it.