NT CLIB: Instead of directly linking to GetEnvironmentStringsA as a
dependency, use GetProcAddress instead. That symbol does not exist on
early Win32s (Windows 3.1) runtimes. On later Win32s runtimes
GetEnvironmentStringsA always returns NULL, added fallback code to call
GetEnvironmentString (without the A) instead which is the only way to
get the environment block on Windows 3.1.