* threads.c: fix various preprocessor usages of new public
symbols to expect 0 or 1 values rather than 1 or undefined.
i.e. change #ifdef to #if, etc.
* null-threads.c: fix various preprocessor usages of new public
symbols to expect 0 or 1 values rather than 1 or undefined.
i.e. change #ifdef to #if, etc.
* coop-threads.c: fix various preprocessor usages of new public
symbols to expect 0 or 1 values rather than 1 or undefined.
i.e. change #ifdef to #if, etc.
* coop-pthreads.c: fix various preprocessor usages of new public
symbols to expect 0 or 1 values rather than 1 or undefined.
i.e. change #ifdef to #if, etc.