Update bazel examples.

Use the simplified repo rules from llvm@934f084.

Reviewed By: GMNGeoffrey

Differential Revision: https://reviews.llvm.org/D108237

Author: chsigg

utils/bazel/examples/http_archive/WORKSPACE

@@ -20,38 +20,24 @@ http_archive(
 )
 
 # Replace with the LLVM commit you want to use.
-LLVM_COMMIT = "09ac97ce350316b95b8cddb796d52f71b6f68296"
+LLVM_COMMIT = "81d5412439efd0860c0a8dd51b831204f118d485"
 
 # The easiest way to calculate this for a new commit is to set it to empty and
 # then run a bazel build and it will report the digest necessary to cache the
 # archive and make the build reproducible.
-LLVM_SHA256 = "2fb1aa06d12f8db349a27426cb0ced062987c5c2a75143c69f4284929e2750ff"
-
-# FIXME: It shouldn't be necessary to use http_archive twice here. Caching
-# should mean that this isn't too expensive though.
+LLVM_SHA256 = "50b3ef31b228ea0c96ae074005bfac087c56e6a4b1c147592dd33f41cad0706b"
 
 http_archive(
-    name = "llvm-project-raw",
-    build_file_content = "#empty",
+    name = "llvm-raw",
+    build_file_content = "# empty",
     sha256 = LLVM_SHA256,
     strip_prefix = "llvm-project-" + LLVM_COMMIT,
     urls = ["https://github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT)],
 )
 
-http_archive(
-    name = "llvm-bazel",
-    sha256 = LLVM_SHA256,
-    strip_prefix = "llvm-project-{}/utils/bazel".format(LLVM_COMMIT),
-    urls = ["https://github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT)],
-)
-
-load("@llvm-bazel//:configure.bzl", "llvm_configure", "llvm_disable_optional_support_deps")
+load("@llvm-raw//utils/bazel:configure.bzl", "llvm_configure", "llvm_disable_optional_support_deps")
 
-llvm_configure(
-    name = "llvm-project",
-    src_path = ".",
-    src_workspace = "@llvm-project-raw//:WORKSPACE",
-)
+llvm_configure(name = "llvm-project")
 
 # Disables optional dependencies for Support like zlib and terminfo. You may
 # instead want to configure them using the macros in the corresponding bzl