Try to modify external gflags to solve CI compilation (#18872)

cmake/external/gflags.cmake

@@ -21,6 +21,8 @@ IF(WIN32)
   set(GFLAGS_LIBRARIES "${GFLAGS_INSTALL_DIR}/lib/gflags_static.lib" CACHE FILEPATH "GFLAGS_LIBRARIES" FORCE)
 ELSE(WIN32)
   set(GFLAGS_LIBRARIES "${GFLAGS_INSTALL_DIR}/lib/libgflags.a" CACHE FILEPATH "GFLAGS_LIBRARIES" FORCE)
+  set(BUILD_COMMAND $(MAKE) --silent)
+  set(INSTALL_COMMAND $(MAKE) install)
 ENDIF(WIN32)
 
 INCLUDE_DIRECTORIES(${GFLAGS_INCLUDE_DIR})
@@ -31,6 +33,8 @@ ExternalProject_Add(
     GIT_REPOSITORY  "https://github.com/gflags/gflags.git"
     GIT_TAG         77592648e3f3be87d6c7123eb81cbad75f9aef5a
     PREFIX          ${GFLAGS_SOURCES_DIR}
+    BUILD_COMMAND   ${BUILD_COMMAND}
+    INSTALL_COMMAND ${INSTALL_COMMAND}
     UPDATE_COMMAND  ""
     CMAKE_ARGS      -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
                     -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
@@ -50,6 +54,7 @@ ExternalProject_Add(
                      -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
                      -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
 )
+
 ADD_LIBRARY(gflags STATIC IMPORTED GLOBAL)
 SET_PROPERTY(TARGET gflags PROPERTY IMPORTED_LOCATION ${GFLAGS_LIBRARIES})
 ADD_DEPENDENCIES(gflags extern_gflags)

paddle/fluid/platform/dynload/CMakeLists.txt

 cc_library(dynamic_loader SRCS dynamic_loader.cc DEPS glog gflags enforce)
-target_link_libraries(dynamic_loader glog gflags enforce)
 
 list(APPEND CUDA_SRCS cublas.cc cudnn.cc curand.cc)