ALSA: hda/hdmi: Cancel pending works before suspend

The per_pin->work might be still floating at the suspend, and this may
hit the access to the hardware at an unexpected timing.  Cancel the
work properly at the suspend callback for avoiding the buggy access.

Note that the bug doesn't trigger easily in the recent kernels since
the work is queued only when the repoll count is set, and usually it's
only at the resume callback, but it's still possible to hit in
theory.

BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1182377
Reported-and-tested-by: Abhishek Sahu <abhsahu@nvidia.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210310112809.9215-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>