powerpc/CoreNet: add tool to support pbl image build.

Provides a tool to build boot Image for PBL(Pre boot loader) which is
used on Freescale CoreNet SoCs, PBL can be used to load some instructions
and/or data for pre-initialization. The default output image is u-boot.pbl,
for more details please refer to doc/README.pblimage.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
diff --git a/tools/Makefile b/tools/Makefile
index a7d1e18..c31437e 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -92,6 +92,7 @@
 OBJ_FILES-$(CONFIG_XWAY_SWAP_BYTES) += xway-swap-bytes.o
 NOPED_OBJ_FILES-y += aisimage.o
 NOPED_OBJ_FILES-y += kwbimage.o
+NOPED_OBJ_FILES-y += pblimage.o
 NOPED_OBJ_FILES-y += imximage.o
 NOPED_OBJ_FILES-y += omapimage.o
 NOPED_OBJ_FILES-y += mkenvimage.o
@@ -208,6 +209,7 @@
 			$(obj)image.o \
 			$(obj)imximage.o \
 			$(obj)kwbimage.o \
+			$(obj)pblimage.o \
 			$(obj)md5.o \
 			$(obj)mkimage.o \
 			$(obj)os_support.o \