[clang] [clang] Absoultify paths in dependency file output (PR #117458)

[Fangrui Song via cfe-commits]

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@@ -47,4 +47,4 @@
 
 // RUN: %clang_cc1 -D REINCLUDE -I %t -ivfsoverlay %t.yaml -Eonly %s -MTfoo -dependency-file %t.dep
 // RUN: cat %t.dep | FileCheck --check-prefix=CHECK-DEP %s
-// CHECK-DEP-NOT: Inputs
+// CHECK-DEP: Inputs
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MaskRay wrote:

`Inputs{{..?}}external-names.h`

https://github.com/llvm/llvm-project/pull/117458