No need for interrupts here. First thing to know, outputs will stay in the state you make them until something makes them change. So no need for this:
Code:
loop:
High sonyled
Goto loop
all you need is
High sonyled. That will keep the led on forever if nothing tells it to turn off. Further in your code, you have trapped the program to never leave the loop.

Next, if you want to "toggle" the led everytime you get the valid pulse, use
Toggle sonyled instead of high sonyled.

Hth.