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

[Aaron Ballman via llvm-commits]

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@@ -295,6 +296,14 @@ add_llvm_component_library(LLVMSupport
   Demangle
   )
 
+# Link icu library if it is an external library.
+if(ICU_FOUND)
+  target_link_libraries(LLVMSupport
+  PRIVATE
+  ${ICU_LIBRARIES}
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AaronBallman wrote:

I think this means we have to include the ICU license notice somewhere, right?

(https://github.com/unicode-org/icu/blob/main/LICENSE says you have the right to use the software "provided that either (a) this copyright and permission notice appear with all copies of the Data
Files or Software, or (b) this copyright and permission notice appear in associated Documentation.")

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