Function spl_stake_pool::instruction::set_preferred_validator

pub fn set_preferred_validator(
    program_id: &Pubkey, 
    stake_pool_address: &Pubkey, 
    staker: &Pubkey, 
    validator_list_address: &Pubkey, 
    validator_type: PreferredValidatorType, 
    validator_vote_address: Option<Pubkey>
) -> Instruction

Creates SetPreferredDepositValidator instruction