add script for building ascent on llnl lassen (#1258)

Author: cyrush

scripts/build_ascent/build_ascent_cuda_lassen.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+module load cmake/3.23.1
+module load gcc/7.3.1
+module load cuda/11.2.0
+
+export CUDA_ARCH=70
+export CUDA_ARCH_VTKM=volta
+
+export CC=$(which gcc)
+export CXX=$(which g++)
+export FTN=$(which gfortran)
+
+env  enable_mpi=ON enable_fortran=ON raja_enable_vectorization=OFF enable_tests=OFF ./build_ascent_cuda.sh