runtime: load sp and pc inside tinygo_longjmp

This is a small change to make it easier to support architectures that
need to restore more than just the sp and pc registers. In particular,
it is needed for the AVR architecture that needs to restore the frame
pointer (Y register).

src/runtime/panic.go

@@ -13,7 +13,7 @@ func trap()
 // Inline assembly stub. It is essentially C longjmp but modified a bit for the
 // purposes of TinyGo. It restores the stack pointer and jumps to the given pc.
 //export tinygo_longjmp
-func tinygo_longjmp(sp, pc unsafe.Pointer)
+func tinygo_longjmp(frame *task.DeferFrame)
 
 // Compiler intrinsic.
 // Returns whether recover is supported on the current architecture.
@@ -26,7 +26,7 @@ func _panic(message interface{}) {
 		if frame != nil {
 			frame.PanicValue = message
 			frame.Panicking = true
-			tinygo_longjmp(frame.JumpSP, frame.JumpPC)
+			tinygo_longjmp(frame)
 			// unreachable
 		}
 	}