Driver enumeration messed up in 0.81

[R. Bernstein]

In 0.81 we added a NetBSD driver. I messed up and mismatched the
emumeration number with the structure that defines them.

As a result the NetBSD, GNU/linux, Solaris, OSX and Win32 driver
mismatch the structure that holds information about them.

(I will be adding a test to make sure this doesn't happen again in the
future.)

I'm Not sure right now if this is a big enough deal to make another
release.