powerpc: mpc85xx: remove P1_P2_RDB boards

These boards are still non-generic boards:
P1011RDB, P1022RDB, P2010RDB, P2020RDB

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Poonam Aggrwal <poonam.aggrwal@freescale.com>
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index 3b201b7..f436a8e 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -12,6 +12,10 @@
 
 Board            Arch        CPU            Commit      Removed     Last known maintainer/contact
 =================================================================================================
+P2020RDB         powerpc     mpc85xx        -           -           Poonam Aggrwal <poonam.aggrwal@freescale.com>
+P2010RDB         powerpc     mpc85xx        -           -
+P1020RDB         powerpc     mpc85xx        -           -
+P1011RDB         powerpc     mpc85xx        -           -
 MPC8360EMDS      powerpc     mpc83xx        -           -           Dave Liu <daveliu@freescale.com>
 MPC8360ERDK      powerpc     mpc83xx        -           -           Anton Vorontsov <avorontsov@ru.mvista.com>
 P3G4             powerpc     74xx_7xx       d928664f    2015-01-16  Wolfgang Denk <wd@denx.de>