target/loongarch: Implement vssrlrn vssrarn

This patch includes:
- VSSRLRN.{B.H/H.W/W.D};
- VSSRARN.{B.H/H.W/W.D};
- VSSRLRN.{BU.H/HU.W/WU.D};
- VSSRARN.{BU.H/HU.W/WU.D};
- VSSRLRNI.{B.H/H.W/W.D/D.Q};
- VSSRARNI.{B.H/H.W/W.D/D.Q};
- VSSRLRNI.{BU.H/HU.W/WU.D/DU.Q};
- VSSRARNI.{BU.H/HU.W/WU.D/DU.Q}.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20230504122810.4094787-29-gaosong@loongson.cn>
5 files changed