Add Extended (ADDE/adde)

Add Extended   XO-form

adde RT,RA,RB (OE=0 Rc=0)
adde. RT,RA,RB (OE=0 Rc=1)
addeo RT,RA,RB (OE=1 Rc=0)
addeo. RT,RA,RB (OE=1 Rc=1)
RT <-- (RA) + (RB) + CA

The sum (RA) + (RB) + CA is placed into register RT.
Special Registers Altered:
CA CA32
CR0 (if Rc=1)
SO OV OV32 (if OE=1)