target-tricore: Add instructions of RRR opcode format

target-tricore: Add instructions of RRR opcode format

Add microcode generator function gen_cond_sub.

Add helper functions:
    * ixmax/ixmin: search for the max/min value and its related index in a
                   vector of 16-bit values.
    * pack: dack two data registers into an IEEE-754 single precision floating
            point format number.
    * dvadj: divide-adjust the result after dvstep instructions.
    * dvstep: divide a reg by a divisor, producing 8-bits of quotient at a time.

OPCM_32_RRR_FLOAT -> OPCM_32_RRR_DIVIDE

Signed-off-by: Bastian Koppelmann <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>