Add a missing PLIST (pho)
@comment $NetBSD: PLIST,v 1.1 2020/10/13 12:08:58 pho Exp $ bin/cabal man/man1/cabal.1 share/doc/x86_64-netbsd-ghc-8.8.4/${PKGNAME}/LICENSE @pkgdir lib/${PKGNAME}/ghc-8.8.4