Avoid creating new -dnf-plugin subpackage

I got cold feet about this. Let's just put it in the main package.
Easier this way.

PackageKit.spec

@@ -52,8 +52,6 @@ Requires: libdnf%{?_isa} >= %{libdnf_version}
 Requires: shared-mime-info
 Requires: systemd
 
-Recommends: %{name}-dnf-plugin = %{version}-%{release}
-
 # functionality moved to udev itself
 Obsoletes: PackageKit-udev-helper < %{version}-%{release}
 Obsoletes: udev-packagekit < %{version}-%{release}
@@ -140,13 +138,6 @@ Requires: %{name}-glib%{?_isa} = %{version}-%{release}
 A simple helper that offers to install new packages on the command line
 using PackageKit.
 
-%package dnf-plugin
-Summary: Install PackageKit dnf plugin
-Requires: %{name}%{?_isa} = %{version}-%{release}
-
-%description dnf-plugin
-A dnf plugin to notify PackageKit to refresh its state.
-
 %prep
 %autosetup -p1
 
@@ -222,6 +213,7 @@ systemctl disable packagekit-offline-update.service > /dev/null 2>&1 || :
 %{_unitdir}/system-update.target.wants/
 %{_libexecdir}/pk-*offline-update
 %{_libdir}/packagekit-backend/libpk_backend_dnf.so
+%pycached %{python3_sitelib}/dnf-plugins/notify_packagekit.py
 
 %files glib
 %{_libdir}/*packagekit-glib2.so.*
@@ -255,8 +247,5 @@ systemctl disable packagekit-offline-update.service > /dev/null 2>&1 || :
 %{_datadir}/vala/vapi/packagekit-glib2.vapi
 %{_datadir}/vala/vapi/packagekit-glib2.deps
 
-%files dnf-plugin
-%pycached %{python3_sitelib}/dnf-plugins/notify_packagekit.py
-
 %changelog
 %autochangelog