stdio.h includes unistd.h

The stdio.h from the LSB SDK includes unistd.h, but that is not the situation
normally:

$ gcc -dD -E /usr/include/stdio.h 2>&1|grep unistd.h

This causes the OCaml [*] compiler to fail to build in asmrun/roots.c because
unistd.h defines a symbol link (), and roots.c defines a typedef {} link.

My workaround is to simply remove the stdio.h include from asmrun/roots.c as
its not actually needed.
I also tried to edit LSB's stdio.h to remove the unistd.h include, but I can't
because off64_t is defined in unistd.h and stdio.h needs it.

[*]
http://caml.inria.fr/download.en.html