RFR: 8305112: RISC-V: Typo fix for RVC description

[David Holmes]

On Wed, 29 Mar 2023 02:07:08 GMT, Xiaolin Zheng <xlinzheng at openjdk.org> wrote:

> Fix trivial typos in the RVC description that may cause confusion. Found in backporting process https://github.com/openjdk/riscv-port-jdk17u/pull/28.
> 
> Thanks,
> Xiaolin

Fine and trivial.

Thanks

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13219#pullrequestreview-1362171921