Unpredictable random seed for Windows (msys2)
Add support for entropy based random seeds for Windows builds. Currently Windows falls back to using time() for setting random seed.
Current patch ignores the random seed generated. ( generate_seed_bcryptgenrandom() does not set it )
New versions that sets the genarated seed to use.
This works fine on msys2.
Msys1 does not have the bcrypt* support needed, so it still falls back to old time based random sources.
Still targeting to S2_6, since we do msys2 builds from that branch too.