Update usage in docs
//! fn main() -> ! {
//! let p = embassy_rp::init(Default::default());
//!
-//! let mut mc = MultiCore::new();
-//! let _ = mc.cores.1.spawn(unsafe { &mut CORE1_STACK.mem }, move || {
+//! spawn_core1(p.CORE1, unsafe { &mut CORE1_STACK }, move || {
//! let executor1 = EXECUTOR1.init(Executor::new());
//! executor1.run(|spawner| unwrap!(spawner.spawn(core1_task())));
//! });
//! executor0.run(|spawner| unwrap!(spawner.spawn(core0_task())));
//! }
//! ```
-//!
use core::mem::ManuallyDrop;
use core::sync::atomic::{compiler_fence, Ordering};
