powerpc: P2041RDB: Remove macro CONFIG_P2041RDB

Use CONFIG_TARGET_P2041RDB instead.

Signed-off-by: York Sun <york.sun@nxp.com>
diff --git a/board/freescale/common/Makefile b/board/freescale/common/Makefile
index 91374ac..6295d1c 100644
--- a/board/freescale/common/Makefile
+++ b/board/freescale/common/Makefile
@@ -65,7 +65,7 @@
 obj-$(CONFIG_LS102XA_STREAM_ID)	+= ls102xa_stream_id.o
 
 # deal with common files for P-series corenet based devices
-obj-$(CONFIG_P2041RDB)	+= p_corenet/
+obj-$(CONFIG_TARGET_P2041RDB)	+= p_corenet/
 obj-$(CONFIG_P3041DS)	+= p_corenet/
 obj-$(CONFIG_P4080DS)	+= p_corenet/
 obj-$(CONFIG_P5020DS)	+= p_corenet/