ASoC: Intel: Skylake: Correct the ssp rate discovery in skl_get_ssp_clks()

The present flag is only set once when one rate has been found to be saved.
This will effectively going to ignore any rate discovered at later time and
based on the code, this is not the intention.

Fixes: bc2bd45b

 ("ASoC: Intel: Skylake: Parse nhlt and register clock device")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20220630065638.11183-2-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>