nixos/doc: fix manpage format

Spaces inside <refname> cause stray double underscore in generated manual pages.

Fixes #70468

(cherry picked from commit 0eaf294)
(cherry picked from commit 26dfb4f)

nixos/doc/manual/man-configuration.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><filename>configuration.nix</filename>
-  </refname><refpurpose>NixOS system configuration specification</refpurpose>
+  <refname><filename>configuration.nix</filename></refname>
+  <refpurpose>NixOS system configuration specification</refpurpose>
  </refnamediv>
  <refsection>
   <title>Description</title>

nixos/doc/manual/man-nixos-build-vms.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-build-vms</command>
-  </refname><refpurpose>build a network of virtual machines from a network of NixOS configurations</refpurpose>
+  <refname><command>nixos-build-vms</command></refname>
+  <refpurpose>build a network of virtual machines from a network of NixOS configurations</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-enter.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-enter</command>
-  </refname><refpurpose>run a command in a NixOS chroot environment</refpurpose>
+  <refname><command>nixos-enter</command></refname>
+  <refpurpose>run a command in a NixOS chroot environment</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-generate-config.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-generate-config</command>
-  </refname><refpurpose>generate NixOS configuration modules</refpurpose>
+  <refname><command>nixos-generate-config</command></refname>
+  <refpurpose>generate NixOS configuration modules</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-install.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-install</command>
-  </refname><refpurpose>install bootloader and NixOS</refpurpose>
+  <refname><command>nixos-install</command></refname>
+  <refpurpose>install bootloader and NixOS</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-option.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-option</command>
-  </refname><refpurpose>inspect a NixOS configuration</refpurpose>
+  <refname><command>nixos-option</command></refname>
+  <refpurpose>inspect a NixOS configuration</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-rebuild.xml

@@ -8,8 +8,8 @@
 <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -->
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-rebuild</command>
-  </refname><refpurpose>reconfigure a NixOS machine</refpurpose>
+  <refname><command>nixos-rebuild</command></refname>
+  <refpurpose>reconfigure a NixOS machine</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>

nixos/doc/manual/man-nixos-version.xml

@@ -7,8 +7,8 @@
   <refmiscinfo class="source">NixOS</refmiscinfo>
  </refmeta>
  <refnamediv>
-  <refname><command>nixos-version</command>
-  </refname><refpurpose>show the NixOS version</refpurpose>
+  <refname><command>nixos-version</command></refname>
+  <refpurpose>show the NixOS version</refpurpose>
  </refnamediv>
  <refsynopsisdiv>
   <cmdsynopsis>