[clang] [clang][modules-driver] Add dependency scan and dependency graph (PR #152770)

[Michael Spencer via cfe-commits]

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@@ -99,5 +100,6 @@ add_clang_library(clangDriver
   LINK_LIBS
   clangBasic
   clangLex
+  clangDependencyScanning
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Bigcheese wrote:

Frontend depends on Driver for the options (because driver and -cc1 options got merged) and for `clang::createInvocation`. I think we should move the options to their own library (clangOptions?). `clang::createInvocation` is harder because it's used by `ASTUnit::LoadFromCommandLine`. I think both of these should move to the driver as the rest of the frontend doesn't use them.

https://github.com/llvm/llvm-project/pull/152770