gnu: docbook-xml-5: Make it the default docbook-xml.

* gnu/packages/docbook.scm (docbook-xml-5): Rename to...
(docbook-xml): ... this, renaming the previous one to...
(docbook-xml-4.5): ... this.
(docbook2x) [inputs]: Replace docbook-xml with docbook-xml-4.5.
* gnu/packages/freedesktop.scm (wayland) [native-inputs]: Likewise.
* gnu/packages/freedesktop.scm (elogind): Likewise.
* gnu/packages/databases.scm (postgresql-15): Likewise.
* gnu/packages/documentation.scm (asciidoc): Likewise.
* gnu/packages/networking.scm (iputils)
[native-inputs]: Replace docbook-xml-5 with docbook-xml.

gnu/packages/databases.scm

@@ -1223,7 +1223,7 @@ and high-availability (HA).")
                 (invoke "make" "postgres.info")
                 (install-file "postgres.info"
                               (string-append #$output "/share/info"))))))))
-    (native-inputs (list docbook-xml docbook2x libxml2 perl texinfo))
+    (native-inputs (list docbook-xml-4.5 docbook2x libxml2 perl texinfo))
     (inputs (list readline `(,util-linux "lib") openssl zlib))
     (home-page "https://www.postgresql.org/")
     (synopsis "Powerful object-relational database system")

gnu/packages/docbook.scm

@@ -50,7 +50,7 @@
   #:use-module (guix build-system trivial)
   #:use-module (guix build-system python))
 
-(define-public docbook-xml-5
+(define-public docbook-xml
   (package
     (name "docbook-xml")
     (version "5.1")
@@ -97,10 +97,9 @@ suited to books and papers about computer hardware and software (though it is
 by no means limited to these applications.)  This package provides XML DTDs.")
     (license (license:x11-style "" "See file headers."))))
 
-(define-public docbook-xml
+(define-public docbook-xml-4.5
   (package
-    (inherit docbook-xml-5)
+    (inherit docbook-xml)
-    (name "docbook-xml")
     (version "4.5")
     (source (origin
               (method url-fetch/zipbomb)
@@ -709,7 +708,7 @@ Detect the differences in markup between two SGML files.
     (build-system gnu-build-system)
     (inputs
      `(("bash-minimal" ,bash-minimal)
-       ("docbook-xml" ,docbook-xml)
+       ("docbook-xml" ,docbook-xml-4.5)
        ("perl" ,perl)
        ("perl-xml-namespacesupport" ,perl-xml-namespacesupport)
        ("perl-xml-parser" ,perl-xml-parser)

gnu/packages/documentation.scm

@@ -166,7 +166,7 @@ release/xsl/current")
     (native-inputs
      (list autoconf))
     (inputs
-     (list python docbook-xml docbook-xsl libxml2 libxslt))
+     (list python docbook-xml-4.5 docbook-xsl libxml2 libxslt))
     (home-page "https://asciidoc.org/")
     (synopsis "Text-based document generation system")
     (description

gnu/packages/freedesktop.scm

@@ -760,7 +760,7 @@ 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)
+     `(("docbook-xml" ,docbook-xml-4.5)
        ("docbook-xml-4.2" ,docbook-xml-4.2)
        ("docbook-xsl" ,docbook-xsl)
        ("gettext" ,gettext-minimal)
@@ -1188,7 +1188,7 @@ Python.")
     (native-inputs
      (append
       (list docbook-xml-4.2
-            docbook-xml
+            docbook-xml-4.5
             docbook-xsl
             graphviz
             doxygen

gnu/packages/networking.scm

@@ -1609,7 +1609,7 @@ intended as a substitute for the PPPStatus and EthStatus projects.")
      `(("gettext" ,gettext-minimal)
        ("pkg-config" ,pkg-config)
        ("docbook-xsl" ,docbook-xsl)
-       ("docbook-xml" ,docbook-xml-5)
+       ("docbook-xml" ,docbook-xml)
        ("libxml2" ,libxml2)          ;for XML_CATALOG_FILES
        ("xsltproc" ,libxslt)))
     (inputs