Introduce -DKOKKOS_HAVE_CUDA_ARCH macro to build to match the value of __CUDA_ARCH__ .
In the example kokkos/core/configure_kokkos.sh we have three architecture options:

CUDA_NVCC_FLAGS="-DKOKKOS_HAVE_CUDA_ARCH=200;-gencode;arch=compute_20,code=sm_20"
// CUDA_NVCC_FLAGS="-DKOKKOS_HAVE_CUDA_ARCH=300;-gencode;arch=compute_30,code=sm_30"
// CUDA_NVCC_FLAGS="-DKOKKOS_HAVE_CUDA_ARCH=350;-gencode;arch=compute_35,code=sm_35"