Rollup merge of #130895 - RalfJung:asm-tests, r=nnethercote

make type-check-4 asm tests about non-const expressions

These tests recently got changed in #129759. I asked the PR author to make the tests read from a `static mut` (rather than just making them "pass"), but I now think that was a mistake: previously the tests failed because the const was not a valid const expression, after the PR they failed because the const failed to evaluate.

So this PR restores the tests to "fail because the const is not a valid const expression". That can be done in a target-independent way so I unified the x86 and aarch64 tests into one.

Cc `@oli-obk` as the original [author](0d88631) of these tests -- not sure if you still remember what they were intended to test.

tests/ui/asm/non-const.rs

@@ -0,0 +1,11 @@
+//@ needs-asm-support
+
+use std::arch::global_asm;
+
+fn main() {}
+
+// Constants must be... constant
+fn non_const_fn(x: i32) -> i32 { x }
+
+global_asm!("/* {} */", const non_const_fn(0));
+//~^ERROR: cannot call non-const fn

tests/ui/asm/non-const.stderr

@@ -0,0 +1,11 @@
+error[E0015]: cannot call non-const fn `non_const_fn` in constants
+  --> $DIR/non-const.rs:10:31
+   |
+LL | global_asm!("/* {} */", const non_const_fn(0));
+   |                               ^^^^^^^^^^^^^^^
+   |
+   = note: calls in constants are limited to constant functions, tuple structs and tuple variants
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0015`.