[llvm] [VectorUtils] Add InterleaveGroup::members() (NFCI) (PR #195122)

[Ramkumar Ramachandra via llvm-commits]

================
@@ -595,6 +597,15 @@ template <typename InstTy> class InterleaveGroup {
     return Members.lookup(Key);
   }
 
+  /// Return an iterator range over the non-null members of this group, in
+  /// index order.
+  auto members() const {
+    return make_filter_range(
+        map_range(seq<uint32_t>(0, Factor),
+                  [this](uint32_t I) { return getMember(I); }),
+        [](InstTy *I) { return I != nullptr; });
----------------
artagnon wrote:

```suggestion
    return make_filter_range(
        map_range(seq<uint32_t>(0, Factor),
                  [this](uint32_t I) { return getMember(I); }),
        not_equal_to(nullptr));
```

https://github.com/llvm/llvm-project/pull/195122