Add `frexp` to `isTriviallyVectorizable`

[farzonl]

Making this vectorizable was out of scope for this work so did not add frexp to isTriviallyVectorizable. We should do a follow up task for this.

Originally posted by @farzonl in #111569 (comment)

If we can make frexp scalarizable then some of the same techniques could be used for vectorization.

[MacDue]

Now that e0e67a6 has landed you should be able to add frexp to isTriviallyVectorizable