ALSA: control: Fix leftover snd_power_unref()

commit fef1ac95 upstream.

One snd_power_unref() was forgotten and left at __snd_ctl_elem_info()
in the previous change for reorganizing the locking order.

Fixes: fcc62b19 ("ALSA: control: Take power_ref lock primarily")
Link: https://github.com/thesofproject/linux/pull/5127
Link: https://patch.msgid.link/20240801064203.30284-1-tiwai@suse.de


Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>