EP88x: remove remainders of dead board

Commit 1b0757e deleted the EP88x entry from boards.cfg file.
But it missed to remove include/configs/EP88x.h and board/ep88x/.

This commit removes them and adds EP88x to README.scrapyard.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Wolfgang Denk <wd@denx.de>
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index 48557c4..7cfb3a3 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -20,6 +20,7 @@
 ns9750dev        arm         arm926ejs      4cfc611     2013-02-28  Markus Pietrek <mpietrek@fsforth.de>
 AMX860           powerpc     mpc860         1b0757e     2012-10-28  Wolfgang Denk <wd@denx.de>
 c2mon            powerpc     mpc855         1b0757e     2012-10-28  Wolfgang Denk <wd@denx.de>
+EP88x            powerpc     mpc885         1b0757e     2012-10-28
 ETX094           powerpc     mpc850         1b0757e     2012-10-28  Wolfgang Denk <wd@denx.de>
 IAD210           powerpc     mpc860         1b0757e     2012-10-28  -
 LANTEC           powerpc     mpc850         1b0757e     2012-10-28  Wolfgang Denk <wd@denx.de>