tcg/mips: implement rotl/rotr ops on MIPS32R2 rotr operations can be optimized on MIPS32 Release 2 using the ROTR and ROTRV instructions. Also implemented rotl operations by subtracting the shift from 32. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>