Cabal revisions of x509-1.6.4

Hackage metadata revisions edit the .cabal file after upload; each diff below is one revision.

 Name:                x509 Version:             1.6.4+x-revision: 1 Description:         X509 reader and writer License:             BSD3 License-file:        LICENSE Cabal-Version:       >=1.8  Library+  -- No instance for (Semigroup DistinguishedName)+  build-depends: base <4.11+   Build-Depends:     base >= 3 && < 5                    , bytestring                    , memory