Use C11CodePrinter for sympy 1.7

C++ may cause problems for CUDA/OpenCL
8 jobs for opencl-to-spirv in 7 minutes and 5 seconds (queued for 4 seconds)
latest
Status Job ID Name Coverage
  Test
passed #458032
docker
build-documentation

00:00:52

passed #458031
docker
flake8-lint

00:00:10

passed #458028
docker
minimal-conda

00:00:20

passed #458029
docker
minimal-sympy-master

00:00:52

passed #458026
win
minimal-windows

00:01:58

manual #458030
AVX cuda11 docker allowed to fail manual
pycodegen-integration
passed #458025
AVX cuda11 docker
tests-and-coverage

00:03:15

passed #458027
AVX cuda11 docker
ubuntu

00:04:50