mpc8xx: remove RPXlite_dw, quantum board support

These boards are old enough and have no maintainers.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index 6d340d5..017c25b 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -11,6 +11,8 @@
 
 Board            Arch        CPU            Commit      Removed     Last known maintainer/contact
 =================================================================================================
+quantum          powerpc     mpc8xx         -           -
+RPXlite_dw       powerpc     mpc8xx         -           -
 qs850            powerpc     mpc8xx         -           -
 qs860t           powerpc     mpc8xx         -           -
 simpc8313        powerpc     mpc83xx        7445207f    2014-06-05  Ron Madrid <info@sheldoninst.com>