ppc/85xx: Simplify the top makefile for 36-bit config for P2020DS

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Makefile

@@ -2518,12 +2518,7 @@ MPC8572DS_config:       unconfig
 
 P2020DS_36BIT_config \
 P2020DS_config:		unconfig
-	@mkdir -p $(obj)include
-	@if [ "$(findstring _36BIT_,$@)" ] ; then \
-		echo "#define CONFIG_PHYS_64BIT" >>$(obj)include/config.h ; \
-		$(XECHO) "... enabling 36-bit physical addressing." ; \
-	fi
-	@$(MKCONFIG) -a P2020DS ppc mpc85xx p2020ds freescale
+	@$(MKCONFIG) -t $(@:_config=) P2020DS ppc mpc85xx p2020ds freescale
 
 P1011RDB_config:	unconfig
 	@mkdir -p $(obj)include

include/configs/P2020DS.h

@@ -27,6 +27,10 @@
 #ifndef __CONFIG_H
 #define __CONFIG_H
 
+#ifdef CONFIG_MK_36BIT
+#define CONFIG_PHYS_64BIT
+#endif
+
 /* High Level Configuration Options */
 #define CONFIG_BOOKE		1	/* BOOKE */
 #define CONFIG_E500		1	/* BOOKE e500 family */