Revert "build-sys: substitute strings in systemd.unit(5)"

This reverts commits c78ab91132
and 185c3be03c.

It is simpler to just use includes...

Makefile-man.am

@@ -896,6 +896,3 @@ MANPAGES_ALIAS += \
 
 
 endif
-
-CLEANFILES += \
-	man/systemd.unit.xml

Makefile.am

@@ -558,7 +558,7 @@ CLEANFILES += \
 
 NON_INDEX_XML_FILES = $(filter-out man/systemd.index.xml,$(XML_FILES))
 
-XML_GLOB = $(wildcard $(top_srcdir)/man/*.xml $(top_srcdir)/man/*.xml.in $(top_builddir)/man/*.xml)
+XML_GLOB = $(wildcard $(top_srcdir)/man/*.xml)
 update-man-list: make-man-rules.py $(XML_GLOB)
 	$(AM_V_GEN)$(PYTHON) $^ > $(top_srcdir)/Makefile-man.tmp
 	$(AM_V_at)mv $(top_srcdir)/Makefile-man.tmp $(top_srcdir)/Makefile-man.am

make-man-rules.py

@@ -21,7 +21,6 @@ from __future__ import print_function
 import xml.etree.ElementTree as tree
 import collections
 import sys
-import os
 
 SECTION = '''\
 MANPAGES += \\
@@ -46,12 +45,6 @@ HEADER = '''\
 
 '''
 
-CLEANFILES = '''\
-
-CLEANFILES += \\
-	{cleanfiles}
-'''
-
 HTML_ALIAS_RULE = '''\
 {}.html: {}.html
 	$(html-alias)
@@ -89,7 +82,7 @@ def create_rules(*xml_files):
 def mjoin(files):
     return ' \\\n\t'.join(sorted(files) or '#')
 
-def make_makefile(rules, cleanfiles):
+def make_makefile(rules):
     return HEADER + '\n'.join(
         (CONDITIONAL if conditional else SECTION).format(
             manpages=mjoin(set(rulegroup.values())),
@@ -101,13 +94,8 @@ def make_makefile(rules, cleanfiles):
                                 for k,v in sorted(rulegroup.items())
                                 if k != v),
             conditional=conditional)
-        for conditional,rulegroup in sorted(rules.items())) + \
-        CLEANFILES.format(cleanfiles=mjoin(cleanfiles))
+        for conditional,rulegroup in sorted(rules.items()))
 
 if __name__ == '__main__':
-    sources = set(sys.argv[1:])
-    basenames = [os.path.basename(source) for source in sources]
-    spares = set([source for source in sources
-                  if os.path.basename(source) + '.in' in basenames])
-    rules = create_rules(*(sources - spares))
-    print(make_makefile(rules, spares), end='')
+    rules = create_rules(*sys.argv[1:])
+    print(make_makefile(rules), end='')

man/.gitignore

@@ -1,5 +1,4 @@
 /systemd.directives.xml
 /systemd.index.xml
-/systemd.unit.xml
 /*.[13578]
 /python-systemd/