Fix build of MSVC with OpenSSL 3.0.0

Fix build of MSVC with OpenSSL 3.0.0

The build scripts of Visual Studio would fail to detect properly a 3.0.0
build as the check on the second digit was failing.  This is adjusted
where needed, allowing the builds to complete.  Note that the MSIs of
OpenSSL mentioned in the documentation have not changed any library
names for Win32 and Win64, making this change straight-forward.

Reported-by: htalaco, via github
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/YW5XKYkq6k7OtrFq@paquier.xyz
Backpatch-through: 9.6