Function split

pub fn split(
    invoke_context: &InvokeContext<'_>,
    transaction_context: &TransactionContext,
    instruction_context: &InstructionContext,
    stake_account_index: IndexOfAccount,
    lamports: u64,
    split_index: IndexOfAccount,
    signers: &HashSet<Pubkey>,
) -> Result<(), InstructionError>