Proposal: log binary data for Solidity

The program_id is not needed on "Program return data: " because it
always preceeded by the program invoke message, so no need to repeat
the program id. Also rename this to "Program return: " since "data"
is redundant.

programs/bpf/rust/log_data/src/lib.rs

@@ -0,0 +1,24 @@
+//! @brief Example Rust-based BPF program that uses sol_log_data syscall
+
+#![cfg(feature = "program")]
+
+use solana_program::{
+    account_info::AccountInfo, entrypoint, entrypoint::ProgramResult, log::sol_log_data,
+    program::set_return_data, pubkey::Pubkey,
+};
+
+entrypoint!(process_instruction);
+#[allow(clippy::cognitive_complexity)]
+fn process_instruction(
+    _program_id: &Pubkey,
+    _accounts: &[AccountInfo],
+    instruction_data: &[u8],
+) -> ProgramResult {
+    let fields: Vec<&[u8]> = instruction_data.split(|e| *e == 0).collect();
+
+    set_return_data(&[0x08, 0x01, 0x44]);
+
+    sol_log_data(&fields);
+
+    Ok(())
+}