Support linking native libraries to cDAC on non-Windows platforms

[max-charlamb]

#111759 adds support for linking native libraries to the cDAC dll on Windows.

Linking libraries in to a NativeAOT SharedLibrary (like the cdacreader.dll) is difficult as the dll does not know where it is located on the system, only the location the entry executable. The only way to access the location of the shared library itself is through OS APIs. See #112290 for more details.

We have gotten around this on Windows by using a static import library and the LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR flag on the native loader.

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