Remove the definition of the `non_extern_c_functions` feature hint, it is not used by anything.

PiperOrigin-RevId: 656341099
Change-Id: Ifb228718074c924f4a5e446a3f26aa0c1eb80d33
diff --git a/bazel/llvm.bzl b/bazel/llvm.bzl
index 69fd6e8..cb1434e 100644
--- a/bazel/llvm.bzl
+++ b/bazel/llvm.bzl
@@ -53,7 +53,7 @@
             executable = False,
         )
 
-LLVM_COMMIT_SHA = "84658fb82b67fc22ecba1560d0cddd09f9104178"
+LLVM_COMMIT_SHA = "58fb51492d9669525662fa269295d85537968569"
 
 def llvm_loader_repository_dependencies():
     # This *declares* the dependency, but it won't actually be *downloaded* unless it's used.
diff --git a/features/BUILD b/features/BUILD
index 5a0cd44..d796760 100644
--- a/features/BUILD
+++ b/features/BUILD
@@ -19,17 +19,6 @@
 )
 
 crubit_feature_hint(
-    name = "non_extern_c_functions",
-    crubit_features = _SUPPORTED_FEATURES + [
-        "non_extern_c_functions",
-    ],
-    visibility = _EXPERIMENTAL_CLIENTS + [
-        "//base/rust:__subpackages__",
-        "//file/base/rust:__subpackages__",
-    ],
-)
-
-crubit_feature_hint(
     name = "experimental",
     crubit_features = _SUPPORTED_FEATURES + [
         "experimental",