nios2: add FORCE for vmlinuz.gz

stable inclusion
from stable-v5.10.157
commit fbe955be268b0fc9205146789178231ad0ab4820
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7MU59

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fbe955be268b0fc9205146789178231ad0ab4820

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[ Upstream commit 869e4ae4 ]

Add FORCE to placate a warning from make:

arch/nios2/boot/Makefile:24: FORCE prerequisite is missing

Fixes: 2fc8483f ("nios2: Build infrastructure")
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Reviewed-by: NMasahiro Yamada <masahiroy@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: Nsanglipeng <sanglipeng1@jd.com>

arch/nios2/boot/Makefile

@@ -20,7 +20,7 @@ $(obj)/vmlinux.bin: vmlinux FORCE
 $(obj)/vmlinux.gz: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,gzip)
 
-$(obj)/vmImage: $(obj)/vmlinux.gz
+$(obj)/vmImage: $(obj)/vmlinux.gz FORCE
 	$(call if_changed,uimage)
 	@$(kecho) 'Kernel: $@ is ready'