[Doc] Add tables for the supported dtypes

[mattduerrmeier]

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This PR adds documentation for the dtype supported by Triton, as per issue #8458. These were added because the supported dtypes are not documented. I've opted to add two tables: one for the floats and one for the integers.

The following data types do not have documentation yet: fp8e4b15, fp8e4b8, and fp8e5b16. I was unable to find information on these variations of FP8.