build error: lstdc++fs changed to fs in the wrong way

[louishust]

$ python3.4 ./configure.py --enable-dpdk --mode=release --static-boost --static-stdc++  --compiler=/opt/scylladb/bin/g++-7.3
$ ninja-build
FAILED: build/debug/tests/tuple_utils_test
/opt/scylladb/bin/g++-7.3  -fsanitize=address -fsanitize=leak -fsanitize=undefined -fno-sanitize=vptr -DSEASTAR_ASAN_ENABLED -O0 -DSEASTAR_DEBUG -DSEASTAR_DEBUG_SHARED_PTR -DSEASTAR_DEFAULT_ALLOCATOR -DSEASTAR_THREAD_STACK_GUARDS -DSEASTAR_NO_EXCEPTION_HACK -DSEASTAR_SHUFFLE_TASK_QUEUE -I/ssd1/seastar/build/debug/gen -I/ssd1/seastar/build/debug/c-ares -s -Lbuild/debug -Lbuild/debug/fmt/fmt -g -Wl,--no-as-needed   -fvisibility=hidden -Wno-attributes -pthread -Wl,-rpath=/opt/scylladb/lib64:/opt/scylladb/lib/gcc/x86_64-redhat-linux/7 -o build/debug/tests/tuple_utils_test build/debug/tests/tuple_utils_test.o -Wl,-Bstatic -lboost_program_options -lboost_system -lboost_filesystem -Wl,-Bdynamic  -lm fs -Wl,-Bstatic -lboost_thread -Wl,-Bdynamic -lcryptopp -lrt -lgnutls -lgnutlsxx -llz4 -lprotobuf -ldl -lgcc_s  -lyaml-cpp -static-libgcc -static-libstdc++ -L/ssd1/seastar/build/dpdk/lib -Wl,--whole-archive -lrte_pmd_vmxnet3_uio -lrte_pmd_i40e -lrte_pmd_ixgbe -lrte_pmd_e1000 -lrte_pmd_ring -lrte_pmd_bnxt -lrte_pmd_cxgbe -lrte_pmd_ena -lrte_pmd_enic -lrte_pmd_fm10k -lrte_pmd_nfp -lrte_pmd_qede -lrte_pmd_sfc_efx -lrte_hash -lrte_kvargs -lrte_mbuf -lrte_ethdev -lrte_eal -lrte_mempool -lrte_mempool_ring -lrte_ring -lrte_cmdline -lrte_cfgfile -Wl,--no-whole-archive -lrt -lm -ldl -lhwloc -lnuma -lpciaccess -lxml2 -lz -lcares-seastar -lfmt -lasan -lubsan  -lyaml-cpp
g++-7.3: error: fs: No such file or directory

[louishust]

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