Split out Rust BPF no-std stuff (#4968)

sdk/bpf/rust/rust-utils/src/lib.rs

@@ -1,20 +1,6 @@
 //! @brief Solana Rust-based BPF program utility functions and types
 
 #![no_std]
-#![feature(allocator_api)]
-#![feature(alloc_error_handler)]
-#![feature(panic_info_message)]
-#![feature(compiler_builtins_lib)]
-#![feature(lang_items)]
-#[lang = "eh_personality"]
-extern "C" fn eh_personality() {}
 
-extern crate compiler_builtins;
-
-pub mod allocator;
 pub mod entrypoint;
 pub mod log;
-pub mod panic;
-
-#[global_allocator]
-static A: allocator::Allocator = allocator::Allocator;