RFR: 8313322: RISC-V: implement MD5 intrinsic [v4]

[Antonios Printezis]

> What the title says. I started with the aarch64 version but changed it quite heavily.
> 
> I haven't done anything with the macro assembler before, so detailed / picky feedback is very welcome!

Antonios Printezis has updated the pull request incrementally with one additional commit since the last revision:

  use roriw for the rotate left operation

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15090/files
  - new: https://git.openjdk.org/jdk/pull/15090/files/01d6e64a..32232492

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15090&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15090&range=02-03

  Stats: 7 lines in 1 file changed: 6 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/15090.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15090/head:pull/15090

PR: https://git.openjdk.org/jdk/pull/15090