Change softlink to hardlink.

Change-Id: I2758f233fc36ffe245de5b3efdd8305093aba2fc
diff --git a/Makefile b/Makefile
index 9834d94..827dcd2 100644
--- a/Makefile
+++ b/Makefile
@@ -336,7 +336,7 @@
 	-E $(EXEC_ADDR) $(NAND_ARGS) -R $(DRAM_REGS_FILE) \
 	u-boot-$(MV_OUTPUT).bin \
 	u-boot-$(MV_OUTPUT)_$(MV_DDR_FREQ)_$(DDR_TYPE)_$(1).bin && \
-	ln -sf u-boot-$(MV_OUTPUT)_$(MV_DDR_FREQ)_$(DDR_TYPE)_$(1).bin \
+	ln -f u-boot-$(MV_OUTPUT)_$(MV_DDR_FREQ)_$(DDR_TYPE)_$(1).bin \
 	u-boot-$(1).bin
 endef