CMake: Fix using numpy variable for the zstandard path

Copy paste error in a5917175d8.

source/creator/CMakeLists.txt

@@ -656,11 +656,11 @@ if(UNIX AND NOT APPLE)
         # Install to the same directory as the source, so debian-like
         # distros are happy with their policy.
         set(_suffix "site-packages")
-        if(${PYTHON_NUMPY_PATH} MATCHES "dist-packages")
+        if(${PYTHON_ZSTANDARD_PATH} MATCHES "dist-packages")
           set(_suffix "dist-packages")
         endif()
         install(
-          DIRECTORY ${PYTHON_NUMPY_PATH}/zstandard
+          DIRECTORY ${PYTHON_ZSTANDARD_PATH}/zstandard
           DESTINATION ${TARGETDIR_VER}/python/${_target_LIB}/python${PYTHON_VERSION}/${_suffix}
           PATTERN ".svn" EXCLUDE
           PATTERN "__pycache__" EXCLUDE           # * any cache *