target/loongarch: Implement vsrlr vsrar

This patch includes:
- VSRLR[I].{B/H/W/D};
- VSRAR[I].{B/H/W/D}.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20230504122810.4094787-25-gaosong@loongson.cn>
5 files changed