drm/i915: Just use icl+ definition for PLANE_WM blocks field

The unused bits on PLANE_WM & co. are hardwired to zero. So no
need to worry about reading the extra bit on pre-icl.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205205056.30081-2-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 737005b..0f15685 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3927,14 +3927,9 @@ static unsigned int skl_cursor_allocation(int num_active)
 static void skl_ddb_entry_init_from_hw(struct drm_i915_private *dev_priv,
 				       struct skl_ddb_entry *entry, u32 reg)
 {
-	u16 mask;
 
-	if (INTEL_GEN(dev_priv) >= 11)
-		mask = ICL_DDB_ENTRY_MASK;
-	else
-		mask = SKL_DDB_ENTRY_MASK;
-	entry->start = reg & mask;
-	entry->end = (reg >> DDB_ENTRY_END_SHIFT) & mask;
+	entry->start = reg & DDB_ENTRY_MASK;
+	entry->end = (reg >> DDB_ENTRY_END_SHIFT) & DDB_ENTRY_MASK;
 
 	if (entry->end)
 		entry->end += 1;