Merge pull request #7053 from typhoonzero/fix_manylinux_build

fix build link rt

paddle/pybind/CMakeLists.txt

@@ -3,6 +3,7 @@ if(WITH_PYTHON)
     SRCS pybind.cc exception.cc protobuf.cc const_value.cc
     DEPS pybind python backward proto_desc paddle_memory executor prune init
     ${GLOB_OP_LIB})
+  target_link_libraries(paddle_pybind rt)
 endif(WITH_PYTHON)
 
 if(WITH_DOC)