Divides variable of linker flags to LDFLAGS-u-boot and LDFLAGS

Linker needs to use the proper endian/bfd flags even when doing partial linking.
LDFLAGS_u-boot sets linker option which is called it when U-boot is built
(u-boot final).
LDFLAGS sets necessary option by partial linking (use in cmd_link_o_target).

CC: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/arch/sh/cpu/sh2/config.mk b/arch/sh/cpu/sh2/config.mk
index 52d5a0f..f2d40aa 100644
--- a/arch/sh/cpu/sh2/config.mk
+++ b/arch/sh/cpu/sh2/config.mk
@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 #
+ENDIANNESS += -EB
+
 PLATFORM_CPPFLAGS += -m3e -mb
 PLATFORM_RELFLAGS += -ffixed-r13
-PLATFORM_LDFLAGS += -EB
+PLATFORM_LDFLAGS += $(ENDIANNESS)