Add documentation for string functions

diff -urNX dontdiff linux-2.4.2/Documentation/DocBook/Makefile linux-willy/Documentation/DocBook/Makefile
@@ -82,6 +82,8 @@
 		$(TOPDIR)/kernel/pm.c \
 		$(TOPDIR)/kernel/ksyms.c \
 		$(TOPDIR)/kernel/kmod.c \
+		$(TOPDIR)/lib/string.c \
+		$(TOPDIR)/lib/vsprintf.c \
 		$(TOPDIR)/net/netsyms.c
  
 kernel-api.sgml: kernel-api.tmpl $(APISOURCES)

diff -urNX dontdiff linux-2.4.2/Documentation/DocBook/kernel-api.tmpl linux-willy/Documentation/DocBook/kernel-api.tmpl
@@ -41,6 +41,16 @@
      </sect1>
   </chapter>
 
+  <chapter id="libc">
+     <title>Basic C Library Functions</title>
+     <sect1><title>String Conversions</title>
+!Ilib/vsprintf.c
+     </sect1>
+     <sect1><title>String Manipulation</title>
+!Ilib/string.c
+     </sect1>
+  </chapter>
+
   <chapter id="mm">
      <title>Memory Management in Linux</title>
      <sect1><title>The Slab Cache</title>