[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
----------------
Bigcheese wrote:

[This change](https://github.com/llvm/llvm-project/pull/161300) would likely conflict with changing `scanDependecnies`, so I'd do it after that lands.

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