Rollup merge of #146178 - folkertdev:static-align, r=jdonszelmann,ralfjung,traviscross

Implement `#[rustc_align_static(N)]` on `static`s

Tracking issue: rust-lang/rust#146177

```rust
#![feature(static_align)]

#[rustc_align_static(64)]
static SO_ALIGNED: u64 = 0;
```

We need a different attribute than `rustc_align` because unstable attributes are tied to their feature (we can't have two unstable features use the same unstable attribute). Otherwise this uses all of the same infrastructure as `#[rustc_align]`.

r? `@traviscross`

Author: matthiaskrgr

tests/pass/static_align.rs

@@ -0,0 +1,14 @@
+#![feature(static_align)]
+
+// When a static uses `align(N)`, its address should be a multiple of `N`.
+
+#[rustc_align_static(256)]
+static FOO: u64 = 0;
+
+#[rustc_align_static(512)]
+static BAR: u64 = 0;
+
+fn main() {
+    assert!(core::ptr::from_ref(&FOO).addr().is_multiple_of(256));
+    assert!(core::ptr::from_ref(&BAR).addr().is_multiple_of(512));
+}