Initial stub of a Makefile and patches for LLVM

Nothing much, but getting some patches from chimera linux that should
work.

patches/llvm/0021-clang-use-strong-stack-protector-by-default.patch

@@ -0,0 +1,28 @@
+From ea82d4de395f920a4c8d13ed9bc152f95c986ded Mon Sep 17 00:00:00 2001
+From: q66 <q66@chimera-linux.org>
+Date: Tue, 2 May 2023 16:23:22 +0200
+Subject: [PATCH 21/29] clang: use strong stack protector by default
+
+---
+ clang/lib/Driver/ToolChains/Linux.h | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/clang/lib/Driver/ToolChains/Linux.h b/clang/lib/Driver/ToolChains/Linux.h
+index 2eb2d0578..80a0b035c 100644
+--- a/clang/lib/Driver/ToolChains/Linux.h
++++ b/clang/lib/Driver/ToolChains/Linux.h
+@@ -63,6 +63,11 @@ public:
+ 
+   const char *getDefaultLinker() const override;
+ 
++  LangOptions::StackProtectorMode
++  GetDefaultStackProtectorLevel(bool KernelOrKext) const override {
++    return LangOptions::SSPStrong;
++  }
++
+ protected:
+   Tool *buildAssembler() const override;
+   Tool *buildLinker() const override;
+-- 
+2.49.0
+