add test that accepts a C-cmse-nonsecure-call function pointer

Author: folkertdev

tests/ui/cmse-nonsecure/cmse-nonsecure-call/callback-as-argument.rs

@@ -0,0 +1,20 @@
+//@ build-pass
+//@ compile-flags: --target thumbv8m.main-none-eabi --crate-type lib
+//@ needs-llvm-components: arm
+#![feature(abi_c_cmse_nonsecure_call, cmse_nonsecure_entry, no_core, lang_items, intrinsics)]
+#![no_core]
+#[lang = "sized"]
+pub trait Sized {}
+#[lang = "copy"]
+pub trait Copy {}
+impl Copy for u32 {}
+
+#[no_mangle]
+pub extern "C-cmse-nonsecure-entry" fn test(
+    f: extern "C-cmse-nonsecure-call" fn(u32, u32, u32, u32) -> u32,
+    a: u32,
+    b: u32,
+    c: u32,
+) -> u32 {
+    f(a, b, c, 42)
+}