This value is more correct, and matches what we read out in the fastboot
code.  Without this, the watermark code will panic after the first mode
setting activity after a fastboot.

v2: fix up HSW ->clock usage too (Ville)
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>