ALSA: firewire-lib: fix uninitialized local variable

ALSA: firewire-lib: fix uninitialized local variable

The function local variable, curr_cycle_time is declared without
initialization. When tracepoints event is not probed, it looks to be
used as is. This commit fixes it. Fortunately, the value of local variable
is not used unless the event is probed, thus this commit is for better
coding.

Reported-by: Dan Carpenter <error27@gmail.com>
Fixes: fef4e61b0b76 ("ALSA: firewire-lib: extend tracepoints event including CYCLE_TIME of 1394 OHCI")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230130141532.102838-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>