[llvm] [RISCV] Sync RISCVSystemOperands.td order/sections with priv-csrs.adoc from riscv-isa-manual. NFC (PR #207803)

[Craig Topper via llvm-commits]

topperc wrote:

> PR to get the rest of AIA into the priv-csrs.adoc [riscv/riscv-isa-manual#3232](https://github.com/riscv/riscv-isa-manual/pull/3232)

That PR landed so I updated this PR.

https://github.com/llvm/llvm-project/pull/207803