Merge pull request #1477 from hjmjohnson/update-ZSTD_LEGACY_SUPPORT

ENH: Update to -DZSTD_LEGACY_SUPPORT=5
diff --git a/build/cmake/CMakeLists.txt b/build/cmake/CMakeLists.txt
index c9dab0d..3b71362 100644
--- a/build/cmake/CMakeLists.txt
+++ b/build/cmake/CMakeLists.txt
@@ -44,7 +44,7 @@
 
 if (ZSTD_LEGACY_SUPPORT)
     message(STATUS "ZSTD_LEGACY_SUPPORT defined!")
-    add_definitions(-DZSTD_LEGACY_SUPPORT=4)
+    add_definitions(-DZSTD_LEGACY_SUPPORT=5)
 else ()
     message(STATUS "ZSTD_LEGACY_SUPPORT not defined!")
     add_definitions(-DZSTD_LEGACY_SUPPORT=0)