* alloca.c (alloca): Undo yesterday's changes, and simply call

* alloca.c (alloca): Undo yesterday's changes, and simply call
malloc directly for storage, and abort if we don't get what we
want.  The situation is much simpler --- just call malloc.  Emacs
has bizarre/evil requirements (signal handlers might malloc unless
you set this global flag, so you have to set the flag around all
calls to malloc) which we are certainly not going to conform to,
so we can do the simple and obvious thing.