Fix W=1 warning. Remove excess function parameter from description

Fixes: 7bc93821 ("ALSA: firewire-lib: split allocation of isochronous resources from establishment of connection")
Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200702193604.169059-13-pierre-louis.bossart@linux.intel.comSigned-off-by: Takashi Iwai <tiwai@suse.de>