[newlib-cygwin] Fix warning about duplicate id in docbook XML

[Jeff Johnston]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=a9d2d7baae28847972fe37753b8d5a6c581ac73e

commit a9d2d7baae28847972fe37753b8d5a6c581ac73e
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Mon May 2 13:55:16 2022 +0100

    Fix warning about duplicate id in docbook XML
    
    ../newlib/libc/libc.xml:22242: element refentry: validity error : ID iconv already defined
        <refentry id="iconv">
    
    Use a separate namespace for chaper ids, to avoid collision between the
    ids for the chapter and function 'iconv', now that iconv documentation
    is generated unconditionally.

Diff:
---
 newlib/doc/chapter-texi2docbook.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/newlib/doc/chapter-texi2docbook.py b/newlib/doc/chapter-texi2docbook.py
index 1a7803091..834a14e7c 100755
--- a/newlib/doc/chapter-texi2docbook.py
+++ b/newlib/doc/chapter-texi2docbook.py
@@ -29,7 +29,7 @@ def main():
             l = l.strip()
             l = l.lower()
             if first_node:
-                print ('<chapter id="%s" xmlns:xi="http://www.w3.org/2001/XInclude">' % l.replace(' ', '_'))
+                print ('<chapter id="%s_chapter" xmlns:xi="http://www.w3.org/2001/XInclude">' % l.replace(' ', '_'))
                 first_node = False
         elif l.startswith("@chapter "):
             l = l.replace("@chapter ", "", 1)