[clang] [flang] [Flang, Clang] Enable and test 'rdynamic' flag (PR #75598)

[Radu Salavat via cfe-commits]

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@@ -7,13 +7,17 @@
 ! RUN: %flang -### --target=x86_64-windows-msvc -rpath /path/to/dir -shared \
 ! RUN:     -static %s 2>&1 | FileCheck \
 ! RUN:     --check-prefixes=MSVC-LINKER-OPTIONS %s
+! RUN: %flang -### --target=aarch64-linux-none -rdynamic %s 2>&1 | FileCheck --check-prefixes=AARCH-LINKER-OPTIONS %s
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Radu2k wrote:

Sounds reasonable, will update soon. Thanks! 

https://github.com/llvm/llvm-project/pull/75598