drm/i915: Check 5/6 DDB split only when sprites are enabled
drm/i915: Check 5/6 DDB split only when sprites are enabled

Using the 5/6 DDB split make sense only when sprites are enabled.
So check that before we waste any cycles computing the merged
watermarks with the 5/6 DDB split.

Signed-off-by: Ville Syrjälä <cd6e8d405ca90be3a03d5427c5b24fbd2d68dcc4@linux.intel.com>
Reviewed-by: Paulo Zanoni <cc0e04a2103c45cd195651d976f79813d0f66bdf@intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs