[llvm] Create a CharSetConverter class with both iconv and icu support (PR #74516)

[Abhina Sree via llvm-commits]

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@@ -258,6 +258,37 @@ if(LLVM_HAS_LOGF128)
   set(LLVM_HAS_LOGF128 "${HAS_LOGF128}")
 endif()
 
+# Check for ICU.
+if(LLVM_ENABLE_ICU)
+  set(LIBRARY_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES})
+  set(CMAKE_FIND_LIBRARY_SUFFIXES ".so")
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abhina-sree wrote:

It sounds like this change will be a bit more involved to get support for Windows SDK, maybe it would be better to be in an additional PR after this one and have someone that works on the Windows platform to help enable that support, I do not have the ability to test on Windows. But if anyone knows how to add support and has the ability to test it out, please let me know and I can add it to this PR!

https://github.com/llvm/llvm-project/pull/74516