Fix version.

DISTVERSION will make a PKGVERSION of 1.1.1.a, which goes backwards:

$ pkg version -t openssl111-1.1.1 openssl111-1.1.1.a

Now, it goes forward:

$ pkg version -t openssl111-1.1.1 openssl111-1.1.1a
<

Pointy hat: brnrd