Generate btf_tag annotations for function parameters.
A field "annotations" is introduced to DILocalVariable, and
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates how
annotations are encoded in IR:
distinct !DILocalVariable(name: "info",, arg: 1, ..., annotations: !10) !10 = !{!11, !12} !11 = !{!"btf_tag", !"a"} !12 = !{!"btf_tag", !"b"}