For CUDA, provide two implementations, one for 11.3.1+ with
new generic API, and one for older csrsm API (deprecated as
of 11.3.1).

For SYCL, complex is not yet supported by the underlying API,
so it is not enabled.

consistent with the rest of gtensor and gt-*

Old API has better performance than generic until 12, and in 12
the old API was also removed. There is a bsrsm2 API which is very
similar and basically is csr when block size=1, which could be explored
for performance comparison, but the generic API seems more likely to
exist for a long time.