Feature Req: Build flag to disable FVM

[snadrus]

Description

rust-fil-proofs are used in chain binaries as well as SP binaries. The SP binaries do not need most of it, for example the FVM runner has no use in SP binaries.

If there is a build flag to make a more optimized binary, this will make for a lighter SP binary, which is helpful to Curio as it bundles together a large set of tools and intends to increase the bundling.

Acceptance criteria

make sp-lib

Risks + pitfalls

Slight increase in complexity

Where to begin

[vmx]

This should be a feature of https://github.com/filecoin-project/filecoin-ffi, right?

[snadrus]

I can move it.