powerpc: yucca: drop redundant CONFIG_SYS_TEXT_BASE from config.mk

The include/configs/yucca.h already has the same define:
    #define	CONFIG_SYS_TEXT_BASE	0xfffb0000

Remove the redundant one from board/amcc/yucca/config.mk.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Stefan Roese <sr@denx.de>
diff --git a/board/amcc/yucca/config.mk b/board/amcc/yucca/config.mk
index 05a4162..53d3f34 100644
--- a/board/amcc/yucca/config.mk
+++ b/board/amcc/yucca/config.mk
@@ -9,12 +9,6 @@
 # AMCC 440SPe Reference Platform (yucca) board
 #
 
-ifeq ($(ramsym),1)
-CONFIG_SYS_TEXT_BASE = 0x07FD0000
-else
-CONFIG_SYS_TEXT_BASE = 0xfffb0000
-endif
-
 PLATFORM_CPPFLAGS += -DCONFIG_440=1
 
 ifeq ($(debug),1)