(patch) enable signals in dynamically loaded Cygwin DLL

[Mumit Khan]

Chris Faylor <cgf@cygnus.com> writes:
> 
> Note that this probably affects tty initialization too.  It's not just
> signals that are affected, it's any thread that is started during DLL
> initialization.  Since CYGWIN=tty implies the creation of several runtime
> threads, I assume that the problem is manifested there as well.
> 

Yes, it does. In fact, one I/O problem I was having (where the dyn
loaded DLL will crash trying to read from the tty) is fixed after 
this.

I believe I've checked all invocations of makethread, and feel that it's
a safe replacement. Please let me know if you have misgivings about the
synchronization, and if so, I can put it back and only enable that if
!dynamically_loaded.

Regards,
Mumit