[csmith-project/csmith] 789a88: Don't test for Windows; test for `lrand48`.

[Eric Eide <eeide@cs.utah.edu>]

  Branch: refs/heads/master
  Home:   https://github.com/csmith-project/csmith
  Commit: 789a88581a3f1ffaf0a23f862e0eccffe6fa3bf8
      https://github.com/csmith-project/csmith/commit/789a88581a3f1ffaf0a23f862e0eccffe6fa3bf8
  Author: Eric Eide <eeide@cs.utah.edu>
  Date:   2017-05-23 (Tue, 23 May 2017)

  Changed paths:
    M CMakeLists.txt
    M cmake_config.h.in
    M config.h.in
    M configure
    M configure.ac
    M src/CMakeLists.txt
    M src/Makefile.am
    M src/Makefile.in

  Log Message:
  -----------
  Don't test for Windows; test for `lrand48`.

In deciding whether or not to compile and link with our implementation
of `lrand48`, don't check for Windows.  Instead, test whether or not
the current platform has `lrand48`!  This is simpler and more direct,
and it seems more likely to work in cases where some Windows-based
environment (Cygwin?) might actually provide `lrand48`.