arm64: move the (z)install rules to arch/arm64/Makefile

Currently, the (z)install targets in arch/arm64/Makefile descend into
arch/arm64/boot/Makefile to invoke the shell script, but there is no
good reason to do so.

arch/arm64/Makefile can run the shell script directly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210729140527.443116-1-masahiroy@kernel.orgSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/Makefile

@@ -165,8 +165,11 @@ Image: vmlinux
 Image.%: Image
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
-zinstall install:
-	$(Q)$(MAKE) $(build)=$(boot) $@
+install: install-image := Image
+zinstall: install-image := Image.gz
+install zinstall:
+	$(CONFIG_SHELL) $(srctree)/$(boot)/install.sh $(KERNELRELEASE) \
+	$(boot)/$(install-image) System.map "$(INSTALL_PATH)"
 
 PHONY += vdso_install
 vdso_install:

arch/arm64/boot/Makefile

@@ -35,11 +35,3 @@ $(obj)/Image.lzma: $(obj)/Image FORCE
 
 $(obj)/Image.lzo: $(obj)/Image FORCE
 	$(call if_changed,lzo)
-
-install:
-	$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
-	$(obj)/Image System.map "$(INSTALL_PATH)"
-
-zinstall:
-	$(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
-	$(obj)/Image.gz System.map "$(INSTALL_PATH)"