kernel-dev, dev-manual: Moved Kernel prep steps

The dev-manual had a place-holder section for getting the
build host ready for using YP and then doing kernel
development.  This stuff is better suited for the actual
kernel development manual.  I moved the section.  Moving
created several broken links in the manual set that had to
be fixed.

In the dev-manual, I updated the introductory list to include
the newly moved kernel stuff.

(From yocto-docs rev: 2e21260bb5f84e9e30eb353ec841d5962e8a7642)

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/kernel-dev/kernel-dev-concepts-appx.xml

@@ -416,8 +416,8 @@
                     Yocto Linux kernel tree.
                     For information on how to clone a Yocto Linux kernel
                     Git repository, see the
-                    "<ulink url='&YOCTO_DOCS_DEV_URL;#local-kernel-files'>Setting Up to Work On a Kernel</ulink>"
-                    section in the Yocto Project Development Manual.
+                    "<link linkend='preparing-the-build-host-to-work-on-the-kernel'>Preparing the Build Host to Work on the Kernel</link>"
+                    section.
                     </para></listitem>
                 <listitem><para>
                     <emphasis>Temporary Source Files from a Build:</emphasis>