target/loongarch: Implement vssrln vssran

This patch includes:
- VSSRLN.{B.H/H.W/W.D};
- VSSRAN.{B.H/H.W/W.D};
- VSSRLN.{BU.H/HU.W/WU.D};
- VSSRAN.{BU.H/HU.W/WU.D};
- VSSRLNI.{B.H/H.W/W.D/D.Q};
- VSSRANI.{B.H/H.W/W.D/D.Q};
- VSSRLNI.{BU.H/HU.W/WU.D/DU.Q};
- VSSRANI.{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: <20230504122810.4094787-28-gaosong@loongson.cn>
5 files changed