core, relay: fix include directory of libzstd

ChangeLog.adoc

@@ -15,6 +15,7 @@ For a list of important changes that require manual actions, please look at rele
 
 Bug fixes::
 
+  * core, relay: fix include directory of libzstd
   * core: add missing mouse events "alt-ctrl-button2" and "alt-ctrl-button3"
   * irc: fix crash in split of IRC message containing a newline if the server is not given
   * python: fix truncation of unsigned long long integer returned by function string_parse_size

src/core/CMakeLists.txt

@@ -92,7 +92,7 @@ include_directories(${GNUTLS_INCLUDE_PATH})
 include_directories(${CURL_INCLUDE_DIRS})
 
 if(ENABLE_ZSTD)
-  include_directories(${ZSTD_INCLUDE_DIRS})
+  include_directories(${LIBZSTD_INCLUDE_DIRS})
 endif()
 
 include_directories("${CMAKE_BINARY_DIR}")

src/plugins/relay/CMakeLists.txt

@@ -51,7 +51,7 @@ list(APPEND LINK_LIBS ${GCRYPT_LDFLAGS})
 list(APPEND LINK_LIBS ${ZLIB_LIBRARY})
 
 if(ENABLE_ZSTD)
-  include_directories(${ZSTD_INCLUDE_DIRS})
+  include_directories(${LIBZSTD_INCLUDE_DIRS})
   list(APPEND LINK_LIBS ${LIBZSTD_LDFLAGS})
 endif()