nixos/doc/md-to-db.sh: handle Docbook inclues in CommonMark

You can do includes like this:

```{=docbook}
<xi:include href="rl-2111.section.xml" />
```

1 files changed, 6 insertions, 2 deletions

diff --git a/nixos/doc/manual/md-to-db.sh b/nixos/doc/manual/md-to-db.sh
index 7949b42e8d81..c7a328b2295d 100755
--- a/nixos/doc/manual/md-to-db.sh
+++ b/nixos/doc/manual/md-to-db.sh
@@ -24,15 +24,19 @@ mapfile -t MD_FILES < <(find . -type f -regex '.*\.md$')
 for mf in ${MD_FILES[*]}; do
   if [ "${mf: -11}" == ".section.md" ]; then
     mkdir -p $(dirname "$OUT/$mf")
+    OUTFILE="$OUT/${mf%".section.md"}.section.xml"
     pandoc "$mf" "${pandoc_flags[@]}" \
-      -o "$OUT/${mf%".section.md"}.section.xml"
+      -o "$OUTFILE"
+    grep -q -m 1 "xi:include" "$OUTFILE" && sed -i 's|xmlns:xlink="http://www.w3.org/1999/xlink"| xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude"|' "$OUTFILE"
   fi
 
   if [ "${mf: -11}" == ".chapter.md" ]; then
     mkdir -p $(dirname "$OUT/$mf")
+    OUTFILE="$OUT/${mf%".chapter.md"}.chapter.xml"
     pandoc "$mf" "${pandoc_flags[@]}" \
       --top-level-division=chapter \
-      -o "$OUT/${mf%".chapter.md"}.chapter.xml"
+      -o "$OUTFILE"
+    grep -q -m 1 "xi:include" "$OUTFILE" && sed -i 's|xmlns:xlink="http://www.w3.org/1999/xlink"| xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude"|' "$OUTFILE"
   fi
 done