target-tricore: Add instructions of RRR1 opcode format, which have 0xa3 as first...

target-tricore: Add instructions of RRR1 opcode format, which have 0xa3 as first opcode

Add helpers:
    * sub64_ssov: subs two 64 bit values and saturates the result.
    * subr_h/_ssov: subs two halfwords from two words in q-format with rounding
                    / and saturates each result independetly.

Add microcode generator:
    * gen_sub64_d: adds two 64 bit values.
    * gen_msub_h/s_h: multiply four halfwords, sub each result left justfied
                      from two word values / and saturate each result.
    * gen_msubm_h/s_h: multiply four halfwords, sub each result left justfied
                       from two words values in q-format / and saturate each
                       result.
    * gen_msubr32/64_h/s_h: multiply four halfwords, sub each result left
                            justfied from two halftwords/words values in q-format
                            / and saturate each result.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>