remove unused gzstream.cmake (#18705)

test=develop

CMakeLists.txt

@@ -150,7 +150,6 @@ include(external/warpctc)   # download, build, install warpctc
 if (NOT WIN32)
 # there is no official support of nccl, cupti in windows
 include(cupti)
-include(external/gzstream)
 endif (NOT WIN32)
 
 if(WITH_PSLIB)

cmake/external/gzstream.cmake

-# Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-include (ExternalProject)
-
-# NOTE: gzstream is needed when linking with ctr reader.
-
-SET(GZSTREAM_SOURCES_DIR ${THIRD_PARTY_PATH}/gzstream)
-SET(GZSTREAM_INSTALL_DIR ${THIRD_PARTY_PATH}/install/gzstream)
-SET(GZSTREAM_INCLUDE_DIR "${GZSTREAM_INSTALL_DIR}/include/" CACHE PATH "gzstream include directory." FORCE)
-
-ExternalProject_Add(
-        extern_gzstream
-        DEPENDS zlib
-        GIT_REPOSITORY "https://github.com/jacquesqiao/gzstream.git"
-        GIT_TAG ""
-        PREFIX          ${GZSTREAM_SOURCES_DIR}
-        UPDATE_COMMAND  ""
-        CONFIGURE_COMMAND ""
-        BUILD_IN_SOURCE 1
-        BUILD_COMMAND   make EXTERN_CPPFLAGS="-I${THIRD_PARTY_PATH}/install/zlib/include" EXTERM_LDFLAGS="-L${THIRD_PARTY_PATH}/install/zlib/lib" -j8
-        INSTALL_COMMAND mkdir -p ${GZSTREAM_INSTALL_DIR}/lib/ && mkdir -p ${GZSTREAM_INSTALL_DIR}/include/
-        && cp ${GZSTREAM_SOURCES_DIR}/src/extern_gzstream/libgzstream.a ${GZSTREAM_INSTALL_DIR}/lib
-        && cp -r ${GZSTREAM_SOURCES_DIR}/src/extern_gzstream/gzstream.h ${GZSTREAM_INSTALL_DIR}/include
-)
-
-ADD_LIBRARY(gzstream STATIC IMPORTED GLOBAL)
-SET_PROPERTY(TARGET gzstream PROPERTY IMPORTED_LOCATION
-        "${GZSTREAM_INSTALL_DIR}/lib/libgzstream.a")
-
-include_directories(${GZSTREAM_INCLUDE_DIR})
-ADD_DEPENDENCIES(gzstream extern_gzstream zlib)