Originally found in the USD branch, but the problem can occur in
any C++ 11 code that uses thread_local.
If the opengl driver spins off any threads in the dllmain function
there is the possibility that they start before the CRT on the main
thread has initialized the locks leading to a crash.
this change delayloads opengl32.dll sidestepping this issue.
This problem has been observed when using the softwaregl mesa/llvmpipe opengl32.dll