Do not add installed pkg into available ones (RhBug:1655605)

When --showduplicates is used with dnf list, do not add packages from
the reinstall_available list to the list of available packages if the
packages are installed. Those packages are already listed in the
installed list and would show up twice and in incorrect section.

https://bugzilla.redhat.com/show_bug.cgi?id=1655605
https://bugzilla.redhat.com/show_bug.cgi?id=1650275
https://bugzilla.redhat.com/show_bug.cgi?id=1671731

dnf/cli/cli.py

@@ -537,7 +537,9 @@ def returnPkgLists(self, pkgnarrow='all', patterns=None,
         ypl = self._do_package_lists(
             pkgnarrow, patterns, ignore_case=True, reponame=reponame)
         if self.conf.showdupesfromrepos:
-            ypl.available += ypl.reinstall_available
+            for pkg in ypl.reinstall_available:
+                if not pkg.installed and not done_hidden_available:
+                    ypl.available.append(pkg)
 
         if installed_available:
             ypl.hidden_available = ypl.available