fdt: arm: Drop device tree padding

The 4KB padding doesn't seem necessary since we don't normally adjust the
control device tree file within U-Boot. Also drop the memory table space.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index bc1421e..9c735c6 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -138,7 +138,8 @@
 
 targets += $(dtb-y)
 
-DTC_FLAGS += -R 4 -p 0x1000
+# Add any required device tree compiler flags here
+DTC_FLAGS +=
 
 PHONY += dtbs
 dtbs: $(addprefix $(obj)/, $(dtb-y))