ALSA: asihpi: Fix potential OOB array access at reading cache

ALSA: asihpi: Fix potential OOB array access at reading cache

find_control() to retrieve a cached info accesses the array with the
given index blindly, which may lead to an OOB array access.
Add a sanity check for avoiding it.

Link: https://sashiko.dev/#/patchset/20260511230121.28606-1-rosenp%40gmail.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20260515085606.242284-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>