Update to latest ctru-sys and toolchain

src/lib.rs

@@ -1,6 +1,4 @@
 #![feature(thread_local)]
-#![feature(const_btree_new)]
-#![feature(let_else)]
 #![allow(non_camel_case_types)]
 #![allow(clippy::missing_safety_doc)]
 

src/thread.rs

@@ -56,7 +56,7 @@ pub unsafe extern "C" fn pthread_create(
     value: *mut libc::c_void,
 ) -> libc::c_int {
     let attr = attr as *const PThreadAttr;
-    let stack_size = (*attr).stack_size as ctru_sys::size_t;
+    let stack_size = (*attr).stack_size;
     let priority = (*attr).priority;
     let processor_id = (*attr).processor_id;