app-misc/cheat: shell-completion, several fixes

- Now making use of the 'shell-completion' eclass
- Removed 'zsh-completion' USE flag (completion is now installed
  undonditionally)
- No longer building manpage since it's pre-built in the release
- Therefore: No longer depending on app-text/pandoc at build time
- Removed weird total blocking of app-shells/zsh-completion. Now
  soft-blocking app-shells/zsh-completion < 0.34.0 because it used to
  install the zsh completion '_cheat' before 0.34.0.

Signed-off-by: Jonas Frei <freijon@pm.me>

app-misc/cheat/cheat-4.3.3-r1.ebuild

@@ -1,9 +1,9 @@
-# Copyright 2019-2021 Gentoo Authors
+# Copyright 2019-2023 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
 
-inherit bash-completion-r1 go-module optfeature
+inherit go-module optfeature shell-completion
 
 DESCRIPTION="cheat allows you to create and view interactive cheatsheets on the command-line"
 HOMEPAGE="https://github.com/cheat/cheat"
@@ -14,17 +14,13 @@ SRC_URI="https://github.com/${PN}/${PN}/archive/${PV}.tar.gz -> ${P}.tar.gz"
 LICENSE="MIT Apache-2.0 BSD BSD-2"
 SLOT="0"
 KEYWORDS="~amd64 ~x86"
-IUSE="man zsh-completion"
+IUSE="man"
 
-RDEPEND="zsh-completion? ( !app-shells/zsh-completions )"
-BDEPEND="man? ( app-text/pandoc )"
+RDEPEND="!<app-shells/zsh-completions-0.34.0"
+BDEPEND=""
 
 src_compile() {
 	ego build -o ${PN} ./cmd/${PN}
-
-	if use man; then
-		pandoc -s -t man doc/${PN}.1.md -o doc/${PN}.1 || die "building manpage failed"
-	fi
 }
 
 src_test() {
@@ -37,13 +33,9 @@ src_install() {
 	use man && doman doc/${PN}.1
 
 	newbashcomp scripts/${PN}.bash ${PN}
-	insinto /usr/share/fish/vendor_completions.d
-	doins scripts/${PN}.fish
+	dofishcomp scripts/${PN}.fish
 
-	if use zsh-completion; then
-		insinto /usr/share/zsh/site-functions
-		newins scripts/${PN}.zsh _cheat
-	fi
+	newzshcomp scripts/${PN}.zsh _${PN}
 }
 
 pkg_postinst() {