Simplified makefile

CC       =  gcc

CXX      =  g++

MPICC    =  mpicc

MPIC++   =  mpiCC

OPTIMIZE = -ggdb3 -O4 -fopenmp -march=native -mavx -mavx2 

OMP_GPU = -ggdb3 -mp=multicore,gpu -gpu=cuda12.0 -gpu=cc86

CUDA_INC = -I/opt/nvidia/hpc_sdk/Linux_x86_64/23.1/cuda/12.0/include

CUDA_LIB = -L/opt/nvidia/hpc_sdk/Linux_x86_64/23.1/cuda/12.0/lib64

FFTW_INCL=

FFTW_LIB=

NVC = /opt/nvidia/hpc_sdk/Linux_x86_64/23.1/compilers/bin/nvc 

NVFLAGS = -O4 -fast -march=native $(OMP_GPU) -mavx -mavx2  

NVLIB = $(CUDA_INC) $(CUDA_LIB) -lcuda -lcudart

NVCC = /opt/nvidia/hpc_sdk/Linux_x86_64/23.1/cuda/12.0/bin/nvcc

OPT_NVCC   = -std=c++17 --generate-code arch=compute_86,code=sm_86 

CFLAGS +=

MPICHLIB =