Add dependency on rlibc

Cargo.lock

@@ -5,6 +5,7 @@ name = "blog_os"
 version = "0.1.0"
 dependencies = [
  "bootloader",
+ "rlibc",
 ]
 
 [[package]]

Cargo.toml

@@ -6,3 +6,4 @@ edition = "2018"
 
 [dependencies]
 bootloader = { git = "https://github.com/rust-osdev/bootloader.git", branch = "Zbuild-std" }
+rlibc = "1.0.0"

src/main.rs

@@ -1,6 +1,8 @@
 #![no_std]
 #![no_main]
 
+extern crate rlibc;
+
 use core::panic::PanicInfo;
 
 static HELLO: &[u8] = b"Hello World!";