uboot-bcm53xx: drop usage of AUTORELEASE

AUTORELEASE has been deprecated from a long time. Drop it and hardcode
the release following the current one present in the downloads
repository.

Link: https://github.com/openwrt/openwrt/pull/20586
Signed-off-by: Christian Marangi <[email protected]>

package/boot/uboot-bcm53xx/Makefile

@@ -2,7 +2,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_VERSION:=2024.01
 PKG_HASH:=b99611f1ed237bf3541bdc8434b68c96a6e05967061f992443cb30aabebef5b3
-PKG_RELEASE:=$(AUTORELEASE)
+PKG_RELEASE:=2
 
 include $(INCLUDE_DIR)/u-boot.mk
 include $(INCLUDE_DIR)/package.mk