generate u-boot.ldr for Blackfin targets

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/config.mk b/config.mk
index 79e5a31..f4312ed 100644
--- a/config.mk
+++ b/config.mk
@@ -121,6 +121,7 @@
 CPP	= $(CC) -E
 AR	= $(CROSS_COMPILE)ar
 NM	= $(CROSS_COMPILE)nm
+LDR	= $(CROSS_COMPILE)ldr
 STRIP	= $(CROSS_COMPILE)strip
 OBJCOPY = $(CROSS_COMPILE)objcopy
 OBJDUMP = $(CROSS_COMPILE)objdump