arm64: zynqmp: Align u-boot-spl.bin for boot.bin creation

Bootrom is not capable to work with non align bootloader partition
that's why it is necessary to align it before boot.bin creation.
The patch is creating new spl/u-boot-spl-align.bin which is used only
for boot.bin.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

scripts/Makefile.spl

@@ -190,7 +190,10 @@ MKIMAGEFLAGS_boot.bin = -T zynqmpimage -R $(srctree)/$(CONFIG_BOOT_INIT_FILE) \
 	-n "$(shell cd $(srctree); readlink -f $(CONFIG_PMUFW_INIT_FILE))"
 endif
 
-spl/boot.bin: $(obj)/u-boot-spl.bin FORCE
+$(obj)/$(SPL_BIN)-align.bin: $(obj)/$(SPL_BIN).bin
+	@dd if=$< of=$@ conv=block,sync bs=4 2>/dev/null;
+
+spl/boot.bin: $(obj)/$(SPL_BIN)-align.bin FORCE
 	$(call if_changed,mkimage)
 endif