Makefile: circular dependency

[knz]

I am currently debugging the Makefile because a fresh clone of the repo does not build any more.

The proximate symptom is that the vendor tree is not ready when the first Go target is being built.

I found the following:

1. Makefile includes build/deps.mk
2. build rule for deps.mk depends on deps.mk.sig
3. build rule for deps.mk.sig depends on variable definitions in Makefile
4. var defs depend on the contents of deps.mk being included at step (1)

It's because of the circular dependency (which make cannot resolve) that the target bin/.submodules-initialized does not get processed properly.

[knz]

I am looking into this.

[knz]

cc @petermattis