[llvm] [MVT][TableGen] Extend Machine Value Type to `uint16_t` (PR #99657)

[Brandon Wu via llvm-commits]

4vtomat wrote:

> Why are there decreases of total bytes and memory usage? I suppose it should increase?
> And please print a comment about the real MVT name since we miss it after VBR encoding.

Total bytes of array actually increases especially for `RISCV`. For runtime memory, I think it's maybe because `SelectionDAG` only exists for very short period of time?

https://github.com/llvm/llvm-project/pull/99657