ASoC: SOF: Intel: hda-stream: Fix incorrect variable used in error message

ASoC: SOF: Intel: hda-stream: Fix incorrect variable used in error message

The dev_err message is reporting an error about capture streams however
it is using the incorrect variable num_playback instead of num_capture.
Fix this by using the correct variable num_capture.

Fixes: a1d1e266b445 ("ASoC: SOF: Intel: Add Intel specific HDA stream operations")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20250902120639.2626861-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>