Require zstd >= 1.4.0

<leoetlino: Dolphin fails to build with zstd 1.3.8.>

CMakeLists.txt

@@ -618,9 +618,9 @@ else()
   add_subdirectory(Externals/liblzma)
 endif()
 
-pkg_search_module(ZSTD QUIET libzstd)
+pkg_check_modules(ZSTD QUIET libzstd>=1.4.0)
 if(ZSTD_FOUND)
-  message(STATUS "Using shared zstd")
+  message(STATUS "Using shared zstd version: " ${ZSTD_VERSION})
 else()
   check_vendoring_approved(zstd)
   message(STATUS "Shared zstd not found, falling back to the static library")