testsuite: continued implementation
fix l2c dst reg decoding

l2c opcodes destination register are coded with one bit and thus
can only a0, a1, b0, b1. The dst register number cannot be from the
high register set.

* include/opcode/tic6x.h: create a new operand type for register
that must ignore the high register bit (RS) in fetch packet header.

* opcodes/tic6x-dis.c: handle the new operand type and don't
offset the register number in this case

* include/opcode/tic6x-opcode-table.h: add OWREG1NORS operand macro
and coerce l2c opcodes with the new type.
fix sx2op opcode using cross path

sx2op instructions can use cross path : remove TIC6X_FLAG_NO_CROSS
and modify the src2 operand to be of type xsint.