ALSA: firewire-digi00x: Drop bogus const type qualifier on dot_scrt()

sound/firewire/digi00x/amdtp-dot.c:67: warning: type qualifiers ignored on function return type

Drop the bogus "const" type qualifier on the return type of dot_scrt()
to fix this.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>