midi: don't write trailing continuation 0xf0 for SysEx

Because our midi messages already have a size, we don't need the 0xf0
continuation terminator. Also having the terminator optionally requires
you to check and strip it if it's there.

The easiest algorithm is to check the first byte for start (0xf0) or
continuation (0xf7) and the last byte for end (0xf7) and that should be
enough to process the messages without having to ever stip the last
byte.

src/modules/module-vban/midi.c

@@ -51,7 +51,7 @@ static void vban_midi_process_playback(void *data)
 			goto done;
 
 		/* the ringbuffer contains series of sequences, one for each
-		 * received packet. This is not share mem so we can use the
+		 * received packet. This is not shared mem so we can use the
 		 * iterator. */
 		SPA_POD_SEQUENCE_FOREACH((struct spa_pod_sequence*)pod, c) {
 #if 0