RFR: 8340880: RISC-V: add t3-t6 alias into assemler_riscv.hpp

[Fei Yang]

On Fri, 4 Oct 2024 08:39:56 GMT, Hamlin Li <mli at openjdk.org> wrote:

> Hi,
> 
> Can you help to review this simple patch to add add t3-t6?
> I also modified some particularly obvious places which use x28-x31 but indeed intending t3-t6, but keep others as it is, because it's more consistent with context code.
> 
> Thanks!

Thanks.

-------------

Marked as reviewed by fyang (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/21349#pullrequestreview-2351259208