message: Fix warnings in alloc_example.rs
diff: #[panic_handler]
  fn panic_handler(_: &core::panic::PanicInfo) -> ! {
  - unsafe {
  core::intrinsics::abort();
  }
  -}
  #[alloc_error_handler]
  fn alloc_error_handler(_: alloc::alloc::Layout) -> ! {
  - unsafe {
  core::intrinsics::abort();
  }
  -}
  #[start]
  fn main(_argc: isize, _argv: *const *const u8) -> isize {
  