[llvm] fix zstd_shared detection on mingw (PR #139945)

[Jameson Nash via llvm-commits]

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@@ -29,11 +29,11 @@ find_package_handle_standard_args(
 )
 
 if(zstd_FOUND)
-  if(zstd_LIBRARY MATCHES "${zstd_STATIC_LIBRARY_SUFFIX}$")
+  if(zstd_LIBRARY MATCHES "${zstd_STATIC_LIBRARY_SUFFIX}$" AND NOT zstd_LIBRARY MATCHES "\\.dll\\.a$")
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vtjnash wrote:

Upstream, the variable used in similar situations appears to be a hard coded list of ".dll.a" combined with CMAKE_FIND_LIBRARY_SUFFIXES:
https://github.com/Kitware/CMake/blob/ede59aac3f28a0ecb535f13bdcb81fbd5c109983/Modules/FindZLIB.cmake#L162-L171

https://github.com/llvm/llvm-project/pull/139945