Compiling without linuxthreads broken

[Kaz Kylheku]

On 8 Jun 2000, Andreas Jaeger wrote:

> stdio-lock.h is not included if we compile without linuxthreads.
> Should we just add an 
> #ifdef _IO_MTSAFE_IO in _IO_list_lock etc?

Already, list_all_lock is used elsewhere in genops.c without problems, because
it is wrapped in #ifdef _IO_MTSAFE_IO. Failing to do the same wrapping in these
new functions is a regrettable oversight on my part.  It's makes sense for new
these locking functions to do nothing if the library is compiled without MT
suport, but to still be there.