Integrate LLVM to llvm/llvm-project@0ab4db419396 (#24868)

Clean integrate – drops the fixups from the LLVM mirror branch:
- Drops the revert of llvm/llvm-project#216984 via
llvm/llvm-project@5715274
- Auto-drops the cherry-pick of llvm/llvm-project@9ebb067a

Signed-off-by: Artem Gindinson <gindinson@roofline.ai>

third_party/llvm-project

diff --git a/third_party/llvm-project b/third_party/llvm-project
index e65959f..0ab4db4 160000
--- a/third_party/llvm-project
+++ b/third_party/llvm-project
@@ -1 +1 @@
-Subproject commit e65959f1684bd2416e8aa2ce684b8c300c381902
+Subproject commit 0ab4db419396839196100494fcce9437403ee7cc