Unable to build prover without CUDA/Metal acceleration

[koxu1996]

I have AMD Radeon RX 580 which cannot be accelerated in Risc0 zkVM, therefore I am building Kairos prover without cuda / metal features enabled.

Errors reported when running cargo build -p kairos-prover-risc0-server:

error[E0432]: unresolved imports `risc0_zkvm::ExecutorEnv`, `risc0_zkvm::Prover`
   --> kairos-prover-risc0-server/src/main.rs:10:18
    |
10  | use risc0_zkvm::{ExecutorEnv, Prover, Receipt};
    |                  ^^^^^^^^^^^  ^^^^^^ no `Prover` in the root
    |                  |
    |                  no `ExecutorEnv` in the root
    |
note: found an item that was configured out
   --> /home/andrew/.cargo/registry/src/index.crates.io-6f17d22bba15001f/risc0-zkvm-1.0.2/src/lib.rs:123:19
    |
123 |             env::{ExecutorEnv, ExecutorEnvBuilder},
    |                   ^^^^^^^^^^^
note: found an item that was configured out
   --> /home/andrew/.cargo/registry/src/index.crates.io-6f17d22bba15001f/risc0-zkvm-1.0.2/src/lib.rs:126:27
    |
126 |                 Executor, Prover, ProverOpts, ReceiptKind,
    |                           ^^^^^^

error[E0433]: failed to resolve: could not find `ExternalProver` in `risc0_zkvm`
   --> kairos-prover-risc0-server/src/main.rs:84:26
    |
84  |         _ => risc0_zkvm::ExternalProver::new(
    |                          ^^^^^^^^^^^^^^ could not find `ExternalProver` in `risc0_zkvm`
    |
note: found an item that was configured out
   --> /home/andrew/.cargo/registry/src/index.crates.io-6f17d22bba15001f/risc0-zkvm-1.0.2/src/lib.rs:125:83
    |
125 |                 bonsai::BonsaiProver, default_executor, default_prover, external::ExternalProver,
    |                                                                                   ^^^^^^^^^^^^^^

Some errors have detailed explanations: E0432, E0433.
For more information about an error, try `rustc --explain E0432`.
error: could not compile `kairos-prover-risc0-server` (bin "kairos-prover-risc0-server") due to 2 previous errors