drm/i915/gvt: add cmd_access to GEN7_HALF_SLICE_CHICKEN1

Linux guest is using this MMIO in lri command. Add cmd_access flag
for this mmio in gvt to avoid error log.

v2: change the mmio address to its macro name
Signed-off-by: NPei Zhang <pei.zhang@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/handlers.c

@@ -1607,7 +1607,7 @@ static int init_generic_mmio_info(struct intel_gvt *gvt)
 	MMIO_D(0x243c, D_ALL);
 	MMIO_DFH(0x7018, D_ALL, F_MODE_MASK, NULL, NULL);
 	MMIO_DFH(HALF_SLICE_CHICKEN3, D_ALL, F_MODE_MASK | F_CMD_ACCESS, NULL, NULL);
-	MMIO_DFH(0xe100, D_ALL, F_MODE_MASK, NULL, NULL);
+	MMIO_DFH(GEN7_HALF_SLICE_CHICKEN1, D_ALL, F_MODE_MASK | F_CMD_ACCESS, NULL, NULL);
 
 	/* display */
 	MMIO_F(0x60220, 0x20, 0, 0, 0, D_ALL, NULL, NULL);