packagekit-cached-metadata.ks: Adapt for livemedia-creator changes

Now that F24 images are made with livemedia-creator instead of
livecd-creator, the kickstart parser has changed; the new kickstart
parser doesn't understand the $INSTALL_ROOT variable we'd been using in
%post --nochroot scripts. This commit fixes this by replacing
$INSTALL_ROOT usage with hardcoded /mnt/sysimage as docs suggest.

While at this, this commit also fixes a case where resolv.conf would be
incorrectly copied if it is a symlink, thanks to dgilmore for pointing
this out.

snippets/packagekit-cached-metadata.ks

@@ -3,7 +3,7 @@
 %post --nochroot
 # Copy over files needed for networking inside the chroot
 for f in /etc/resolv.conf /etc/hosts ; do
-  test -f $f && cp -a $f ${INSTALL_ROOT}${f}.kickstart
+  test -f $f && cp $f /mnt/sysimage/$f.kickstart
 done
 %end