ALSA: firewire-lib: fix inverted node IDs for amdtp_packet events

The amdtp_packet events have inverted node IDs for src/dst. This commit
fixes the bug.

Fixes: 8d3f1fdf

 ("ALSA: firewire-lib: unify tracing events to 'amdtp_packet' event")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>