intrinsics: use const generic to set atomic ordering

compiler/rustc_error_codes/src/error_codes/E0092.md

@@ -1,8 +1,10 @@
+#### Note: this error code is no longer emitted by the compiler.
+
 An undefined atomic operation function was declared.
 
 Erroneous code example:
 
-```compile_fail,E0092
+```ignore (no longer emitted)
 #![feature(intrinsics)]
 #![allow(internal_features)]
 
@@ -12,13 +14,4 @@ unsafe fn atomic_foo(); // error: unrecognized atomic operation
 ```
 
 Please check you didn't make a mistake in the function's name. All intrinsic
-functions are defined in `compiler/rustc_codegen_llvm/src/intrinsic.rs` and in
-`library/core/src/intrinsics.rs` in the Rust source code. Example:
-
-```
-#![feature(intrinsics)]
-#![allow(internal_features)]
-
-#[rustc_intrinsic]
-unsafe fn atomic_fence_seqcst(); // ok!
-```
+functions are defined in `library/core/src/intrinsics` in the Rust source code.

compiler/rustc_error_codes/src/error_codes/E0093.md

@@ -17,19 +17,4 @@ fn main() {
 ```
 
 Please check you didn't make a mistake in the function's name. All intrinsic
-functions are defined in `compiler/rustc_codegen_llvm/src/intrinsic.rs` and in
-`library/core/src/intrinsics.rs` in the Rust source code. Example:
-
-```
-#![feature(intrinsics)]
-#![allow(internal_features)]
-
-#[rustc_intrinsic]
-unsafe fn atomic_fence_seqcst(); // ok!
-
-fn main() {
-    unsafe {
-        atomic_fence_seqcst();
-    }
-}
-```
+functions are defined in `library/core/src/intrinsics` in the Rust source code.

compiler/rustc_error_codes/src/error_codes/E0622.md

@@ -4,7 +4,7 @@ An intrinsic was declared without being a function.
 
 Erroneous code example:
 
-```no_run
+```ignore (no longer emitted)
 #![feature(intrinsics)]
 #![allow(internal_features)]
 
@@ -21,7 +21,7 @@ An intrinsic is a function available for use in a given programming language
 whose implementation is handled specially by the compiler. In order to fix this
 error, just declare a function. Example:
 
-```no_run
+```ignore (no longer emitted)
 #![feature(intrinsics)]
 #![allow(internal_features)]