update compilation instructions

Author: lucafedeli88

Docs/source/install/hpc/fugaku.rst

@@ -83,7 +83,7 @@ Use the following :ref:`cmake commands <building-cmake>` to compile the applicat
    cmake -S . -B build -DWarpX_COMPUTE=OMP \
        -DWarpX_DIMS="1;2;3" \
        -DCMAKE_BUILD_TYPE=Release \
-       -DCMAKE_CXX_FLAGS_RELEASE="-Ofast -mllvm -polly -mllvm -polly-parallel" \
+       -DCMAKE_CXX_FLAGS_RELEASE="-Ofast" \
        -DAMReX_DIFFERENT_COMPILER=ON \
        -DWarpX_MPI_THREAD_MULTIPLE=OFF