[clang] Fix preprocessed block comment newline on windows containing extra carriage return (PR #205084)

[Joe Kirchoff via cfe-commits]

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@@ -0,0 +1,9 @@
+// RUN: %{to-crlf} %S/Inputs/comment_save_crlf.h > %t.h
+
+// Verify that prepared header contains \r
+// RUN: tr -d '\n' < %t.h | %{reveal-cr} | FileCheck %s --check-prefix=SANITY
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Rinn wrote:

the reveal-cr is only replacing extra unmatched carriage returns with <CR> so this strips out the \n in the string

https://github.com/llvm/llvm-project/pull/205084