drm/i915/cnl: Add Gen10 LRC size

The total size of the context has decreased with the removal of the
URB_ATOMIC section. BSpec indicates 16750 DWORDs (17 pages), plus
one page for PPHWSP, and I'm throwing an extra page for precaution.
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1506035989-14295-1-git-send-email-oscar.mateo@intel.com

drivers/gpu/drm/i915/intel_engine_cs.c

@@ -39,6 +39,7 @@
 
 #define GEN8_LR_CONTEXT_RENDER_SIZE	(20 * PAGE_SIZE)
 #define GEN9_LR_CONTEXT_RENDER_SIZE	(22 * PAGE_SIZE)
+#define GEN10_LR_CONTEXT_RENDER_SIZE	(19 * PAGE_SIZE)
 
 #define GEN8_LR_CONTEXT_OTHER_SIZE	( 2 * PAGE_SIZE)
 
@@ -150,6 +151,7 @@ __intel_engine_context_size(struct drm_i915_private *dev_priv, u8 class)
 		default:
 			MISSING_CASE(INTEL_GEN(dev_priv));
 		case 10:
+			return GEN10_LR_CONTEXT_RENDER_SIZE;
 		case 9:
 			return GEN9_LR_CONTEXT_RENDER_SIZE;
 		case 8: