ALSA: dice: fix wrong offsets for Dice interface

For received packet stream, the offset of 'RX_SEQ_START' locates after
the offset of 'RX_NUMBER_MIDI', although current macro and proc output
includes wrong offsets.

Fortunately, this bug doesn't affect streaming functionality because
these macro is not used.

This commit fixes these wrong macro and outputs.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>