target/mips/mxu: Add Q16ACC Q16ACCM D16ASUM instructions

These instructions are all dual 16-bit addition/subtraction in
various combinations. The instructions are grouped in pool13,
see the opcode organization in the file.

Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
Message-Id: <20230608104222.1520143-19-lis8215@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
1 file changed