add x86-sse2 (32bit) ABI that requires SSE2 target feature

Author: RalfJung

tests/pass/shims/x86/intrinsics-x86-pause-without-sse2.stderr

@@ -0,0 +1,5 @@
+warning: target feature `sse2` must be enabled to ensure that the ABI of the current target can be implemented correctly
+   |
+   = note: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #116344 <https://github.com/rust-lang/rust/issues/116344>
+