drm/i915/tgl: Disable read-only ppgtt support

The same read-only affliction as befell Icelake is affecting Tigerlake.
Disable the read-only support as clearly it was not fixed.

Testcase: igt/i915_selftests/live_gem_context
References: 3936867d ("drm/i915: Disable read only ppgtt support for gen11")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190911125717.28997-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -1486,8 +1486,10 @@ static struct i915_ppgtt *gen8_ppgtt_create(struct drm_i915_private *i915)
 	 *
 	 * Gen11 has HSDES#:1807136187 unresolved. Disable ro support
 	 * for now.
+	 *
+	 * Gen12 has inherited the same read-only fault issue from gen11.
 	 */
-	ppgtt->vm.has_read_only = INTEL_GEN(i915) != 11;
+	ppgtt->vm.has_read_only = !IS_GEN_RANGE(i915, 11, 12);
 
 	/* There are only few exceptions for gen >=6. chv and bxt.
 	 * And we are not sure about the latter so play safe for now.