gnu: elogind: Drop input labels and fix indentation.

* gnu/packages/freedesktop.scm (elogind): Re-indent package.
[native-inputs]: Remove labels.

gnu/packages/freedesktop.scm

@@ -754,16 +754,16 @@ the freedesktop.org XDG Base Directory specification.")
              (substitute* "src/login/elogind.c"
                (("\"/run/elogind.pid\"") "\"/run/systemd/elogind.pid\"")))))))
     (native-inputs
-     `(("docbook-xml" ,docbook-xml-4.5)
+     (list docbook-xml-4.5
-       ("docbook-xml-4.2" ,docbook-xml-4.2)
+           docbook-xml-4.2
-       ("docbook-xsl" ,docbook-xsl)
+           docbook-xsl
-       ("gettext" ,gettext-minimal)
+           gettext-minimal
-       ("gperf" ,gperf)
+           gperf
-       ("libxml2" ,libxml2)                     ;for XML_CATALOG_FILES
+           libxml2                      ;for XML_CATALOG_FILES
-       ("m4" ,m4)
+           m4
-       ("pkg-config" ,pkg-config)
+           pkg-config
-       ("python" ,python)
+           python
-       ("xsltproc" ,libxslt)))
+           libxslt))
     (inputs
      (append
       (if (not (target-riscv64?))