fix(network-manager): always install the library plugins directory

The library plugins directory is automatically added to the initrd if either
libnm-device-plugin-team.so or libnm-settings-plugin-ifcfg-rh.so are present on
the system, but both are optional libraries, and if it does not exist, the
NetworkManager issues a warning.

modules.d/35network-manager/module-setup.sh

@@ -61,6 +61,7 @@ install() {
     inst_hook initqueue/settled 99 "$moddir/nm-run.sh"
 
     inst_rules 85-nm-unmanaged.rules
+    inst_libdir_dir "NetworkManager/$_nm_version"
     inst_libdir_file "NetworkManager/$_nm_version/libnm-device-plugin-team.so"
     inst_simple "$moddir/nm-lib.sh" "/lib/nm-lib.sh"