zynq-boot-bin: use HOST_ZYNQ_BOOT_BIN_DL_DIR instead of ZYNQ_BOOT_BIN_DL_DIR

The infrastructure only provides HOST_ZYNQ_BOOT_BIN_DL_DIR, because this
package is host only. Ideally the infra should provide ZYNQ_BOOT_BIN_DL_DIR,
but it doesn't currently, and that requires more significant changes.

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/zynq-boot-bin/zynq-boot-bin.mk

@@ -12,7 +12,7 @@ ZYNQ_BOOT_BIN_LICENSE = GPL-3.0+
 HOST_ZYNQ_BOOT_BIN_DEPENDENCIES = host-python
 
 define HOST_ZYNQ_BOOT_BIN_EXTRACT_CMDS
-	cp $(ZYNQ_BOOT_BIN_DL_DIR)/$(ZYNQ_BOOT_BIN_SOURCE) $(@D)
+	cp $(HOST_ZYNQ_BOOT_BIN_DL_DIR)/$(ZYNQ_BOOT_BIN_SOURCE) $(@D)
 endef
 
 define HOST_ZYNQ_BOOT_BIN_INSTALL_CMDS