Partially fix 2001/bellard

This still crashes and may very well not work even if it doesn't but I
cannot determine that. I just fixed the initial segfault when opening
the file. I believe it will take much debugging, a 32-bit system to test
it on and also a knowledge of the ELF format. There might be other
things but I believe those are the minimum requirements.

I did fix the supplementary program bellard.otccex.c so it does not
segfault and seemingly it works too (I didn't really evaluate that the
output is correct but it does process the args anyway).

I updated bugs.md to note that this entry does not work and any help
would be appreciated.

2001/bellard/.gitignore

@@ -1 +1,2 @@
 bellard
+bellard.otccex