Makefile: Add required dependencies

Some of the targets rely on others but weren't actually listed:

- init relies on containerization as it invokes cctl.
- integration relies on init as it needs the rootfs with vminitd inside.

Author: dcantah

Makefile

@@ -54,7 +54,7 @@ containerization:
 	@codesign --force --sign - --timestamp=none --entitlements=signing/vz.entitlements bin/containerization-integration
 
 .PHONY: init
-init: vminitd
+init: containerization vminitd
 	@echo Creating init.ext4...
 	@rm -f bin/init.rootfs.tar.gz bin/init.block
 	@./bin/cctl rootfs create --vminitd vminitd/bin/vminitd --labels org.opencontainers.image.source=https://github.com/apple/containerization --vmexec vminitd/bin/vmexec bin/init.rootfs.tar.gz vminit:latest
@@ -83,7 +83,7 @@ test:
 	@$(SWIFT) test --enable-code-coverage
 
 .PHONY: integration
-integration:
+integration: init
 ifeq (,$(wildcard bin/vmlinux))
 	@echo No bin/vmlinux kernel found. See fetch-default-kernel target.
 	@exit 1