mpc8xx: remove KUP4X, KUP4K board support

These boards are still non-generic boards.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Klaus Heydeck <heydeck@kieback-peter.de>
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index 426cadc..3a27d4c 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -12,6 +12,8 @@
 
 Board            Arch        CPU            Commit      Removed     Last known maintainer/contact
 =================================================================================================
+KUP4K            powerpc     mpc8xx         -           -           Klaus Heydeck <heydeck@kieback-peter.de>
+KUP4X            powerpc     mpc8xx         -           -           Klaus Heydeck <heydeck@kieback-peter.de>
 ELPT860          powerpc     mpc8xx         -           -           The LEOX team <team@leox.org>
 hmi1001          powerpc     mpc5xxx        -           -
 mucmc52          powerpc     mpc5xxx        -           -           Heiko Schocher <hs@denx.de>