drm/i915/mtl: Fix bcs default context

Commit 0d0e7d1e ("drm/i915/mtl: Define engine context layouts")
added the engine context for Meteor Lake. In a second revision of the
patch it was believed the xcs offsets were wrong due to a tagging
issue in the spec. The first version was actually correct, as shown
by the intel_lrc_live_selftests/live_lrc_layout test:

	i915: Running gt_lrc
	i915: Running intel_lrc_live_selftests/live_lrc_layout
	bcs0: LRI command mismatch at dword 1, expected 1108101d found 11081019
	[drm:drm_helper_probe_single_connector_modes [drm_kms_helper]] [CONNECTOR:236:DP-1] disconnected
	bcs0: HW register image:
	[0000] 00000000 1108101d 00022244 ffff0008 00022034 00000088 00022030 00000088
	...
	bcs0: SW register image:
	[0000] 00000000 11081019 00022244 00090009 00022034 00000000 00022030 00000000

The difference in the 2 additional dwords (0x1d vs 0x19) are the offsets
 0x120 / 0x124 that are indeed part of the context image.

Bspec: 45585

Fixes: 0d0e7d1e ("drm/i915/mtl: Define engine context layouts")
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230111235531.3353815-2-radhakrishna.sripada@intel.com
(cherry picked from commit ca54a9a3)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/gt/intel_lrc.c

@@ -288,39 +288,6 @@ static const u8 dg2_xcs_offsets[] = {
 	END
 };
 
-static const u8 mtl_xcs_offsets[] = {
-	NOP(1),
-	LRI(13, POSTED),
-	REG16(0x244),
-	REG(0x034),
-	REG(0x030),
-	REG(0x038),
-	REG(0x03c),
-	REG(0x168),
-	REG(0x140),
-	REG(0x110),
-	REG(0x1c0),
-	REG(0x1c4),
-	REG(0x1c8),
-	REG(0x180),
-	REG16(0x2b4),
-	NOP(4),
-
-	NOP(1),
-	LRI(9, POSTED),
-	REG16(0x3a8),
-	REG16(0x28c),
-	REG16(0x288),
-	REG16(0x284),
-	REG16(0x280),
-	REG16(0x27c),
-	REG16(0x278),
-	REG16(0x274),
-	REG16(0x270),
-
-	END
-};
-
 static const u8 gen8_rcs_offsets[] = {
 	NOP(1),
 	LRI(14, POSTED),
@@ -739,9 +706,7 @@ static const u8 *reg_offsets(const struct intel_engine_cs *engine)
 		else
 			return gen8_rcs_offsets;
 	} else {
-		if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 70))
-			return mtl_xcs_offsets;
-		else if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 55))
+		if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 55))
 			return dg2_xcs_offsets;
 		else if (GRAPHICS_VER(engine->i915) >= 12)
 			return gen12_xcs_offsets;