[Nek5000#305][Hotfix] Don't cross-compile OCCA kernel launchers unles…

…s in serial mode.

scripts/nrsqsub_summit

@@ -15,16 +15,18 @@ fi
 : ${NEKRS_HOME:="$HOME/.local/nekrs"}
 : ${OCCA_CACHE_DIR:="$PWD/.cache/occa"}
 NVME_HOME="/mnt/bb/$USER/"
-XL_HOME="/sw/summit/xl/16.1.1-3/xlC/16.1.1"
+XL_HOME="/sw/summit/xl/16.1.1-9/xlC/16.1.1"
 
 : ${CPUONLY:=0}
 export NEKRS_HOME
 export OCCA_CACHE_DIR
 export NEKRS_HYPRE_NUM_THREADS=1
 export NEKRS_GPU_MPI=1
-export OCCA_CXX="$XL_HOME/bin/xlc" 
-export OCCA_CXXFLAGS="-O3 -qarch=pwr9 -qhot -DUSE_OCCA_MEM_BYTE_ALIGN=64" 
-export OCCA_LDFLAGS="$XL_HOME/lib/libibmc++.a"
+if [ $CPUONLY -eq 1 ]; then
+  export OCCA_CXX="$XL_HOME/bin/xlc" 
+  export OCCA_CXXFLAGS="-O3 -qarch=pwr9 -qhot -DUSE_OCCA_MEM_BYTE_ALIGN=64" 
+  export OCCA_LDFLAGS="$XL_HOME/lib/libibmc++.a"
+fi
 
 #export OMPI_LD_PRELOAD_POSTPEND=$OLCF_SPECTRUM_MPI_ROOT/lib/libmpitrace.so