Auto merge of #89937 - JohnTitor:fix-89875, r=Amanieu

Properly check `target_features` not to trigger an assertion

Fixes #89875
I think it should be a condition instead of an assertion to check if it's a register as it's possible that `reg` is a register class.
Also, this isn't related to the issue directly, but `is_target_supported` doesn't check `target_features` attributes. Is there any way to check it on rustc_codegen_llvm?

r? `@Amanieu`

src/test/ui/asm/x86_64/issue-89875.rs

@@ -0,0 +1,14 @@
+// build-pass
+// only-x86_64
+
+#![feature(asm, target_feature_11)]
+
+#[target_feature(enable = "avx")]
+fn main() {
+    unsafe {
+        asm!(
+            "/* {} */",
+            out(ymm_reg) _,
+        );
+    }
+}