SelectionDAG: Get libcall info from analysis, not TargetLowering (#239827)

TargetLowering's copy of the libcall info will eventually be
removed. Use the LibcallLoweringInfo analysis from SelectionDAG
instead.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
GitOrigin-RevId: aa1a146d10dceceb6a3e3de048a2160b66fcd13d
5 files changed