Bug 1812214 - Stop passing libtool to cmake when building clang. r=firefox-build-system-reviewers,sergesanspaille

It's not used anyway:
```
CMake Warning:
  Manually-specified variables were not used by the project:
    CMAKE_LIBTOOL
```

Differential Revision: https://phabricator.services.mozilla.com/D167753

build/build-clang/README

@@ -34,7 +34,6 @@ build-clang.py accepts a JSON config format with the following fields:
 * as: Path to the assembler tool.
 * ar: Path to the library archiver tool.
 * ranlib: Path to the ranlib tool (optional).
-* libtool: Path to the libtool tool (optional).
 * ld: Path to the linker.
 * patches: Optional list of patches to apply.
 * build_type: The type of build to make.  Supported types: Release, Debug, RelWithDebInfo or MinSizeRel.

build/build-clang/build-clang.py

@@ -177,7 +177,6 @@ def build_one_stage(
     asm,
     ar,
     ranlib,
-    libtool,
     ldflags,
     src_dir,
     stage_dir,
@@ -199,7 +198,7 @@ def build_one_stage(
     def slashify_path(path):
         return path.replace("\\", "/")
 
-    def cmake_base_args(cc, cxx, asm, ar, ranlib, libtool, ldflags, inst_dir):
+    def cmake_base_args(cc, cxx, asm, ar, ranlib, ldflags, inst_dir):
         machine_targets = targets if is_final_stage and targets else "X86"
 
         cmake_args = [
@@ -259,8 +258,6 @@ def build_one_stage(
             cmake_args += ["-DLLVM_LINK_LLVM_DYLIB=ON"]
         if ranlib is not None:
             cmake_args += ["-DCMAKE_RANLIB=%s" % slashify_path(ranlib)]
-        if libtool is not None:
-            cmake_args += ["-DCMAKE_LIBTOOL=%s" % slashify_path(libtool)]
         if osx_cross_compile:
             arch = "arm64" if os.environ.get("OSX_ARCH") == "arm64" else "x86_64"
             target_cpu = (
@@ -313,7 +310,7 @@ def build_one_stage(
         return cmake_args
 
     cmake_args = []
-    cmake_args += cmake_base_args(cc, cxx, asm, ar, ranlib, libtool, ldflags, inst_dir)
+    cmake_args += cmake_base_args(cc, cxx, asm, ar, ranlib, ldflags, inst_dir)
     cmake_args += [src_dir]
     build_package(build_dir, cmake_args)
 
@@ -606,9 +603,6 @@ def main():
     # knows how to find it when they are installed alongside each others.
     ar = get_tool(config, "lib" if is_windows() else "ar")
     ranlib = None if is_windows() else get_tool(config, "ranlib")
-    libtool = None
-    if "libtool" in config:
-        libtool = get_tool(config, "libtool")
 
     if not os.path.exists(source_dir):
         os.makedirs(source_dir)
@@ -725,7 +719,6 @@ def main():
             [asm] + extra_asmflags,
             ar,
             ranlib,
-            libtool,
             extra_ldflags,
             llvm_source_dir,
             stage1_dir,
@@ -751,7 +744,6 @@ def main():
             [asm] + extra_asmflags,
             ar,
             ranlib,
-            libtool,
             extra_ldflags,
             llvm_source_dir,
             stage2_dir,
@@ -778,7 +770,6 @@ def main():
             [asm] + extra_asmflags,
             ar,
             ranlib,
-            libtool,
             extra_ldflags,
             llvm_source_dir,
             stage3_dir,
@@ -821,7 +812,6 @@ def main():
             [asm] + extra_asmflags,
             ar,
             ranlib,
-            libtool,
             extra_ldflags,
             llvm_source_dir,
             stage4_dir,

build/build-clang/clang-tidy-macosx64.json

@@ -7,7 +7,6 @@
     "as": "{MOZ_FETCHES_DIR}/clang/bin/clang",
     "ar": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-ar",
     "ranlib": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-ranlib",
-    "libtool": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-libtool",
     "ld": "{MOZ_FETCHES_DIR}/clang/bin/clang",
     "patches": [
         "clang_include_cleaner.patch",

build/build-clang/macosx64.json

@@ -5,6 +5,5 @@
     "as": "{MOZ_FETCHES_DIR}/clang/bin/clang",
     "ar": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-ar",
     "ranlib": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-ranlib",
-    "libtool": "{MOZ_FETCHES_DIR}/cctools/bin/x86_64-apple-darwin-libtool",
     "ld": "{MOZ_FETCHES_DIR}/clang/bin/clang"
 }