drm/xe: Add few more GT register definitions

While we are not using these registers right now, they are part
of some runtime register lists that PF driver share with VFs on
some legacy platforms that we might want to support as SDV.

Reviewed-by: Piotr Piórkowski <[e-mail]>
Signed-off-by: Michal Wajdeczko <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/xe/regs/xe_gt_regs.h

···
 #define   MAX_MSLICES				4
 #define   MEML3_EN_MASK				REG_GENMASK(3, 0)
 
+#define MIRROR_FUSE1				XE_REG(0x911c)
+
 #define XELP_EU_ENABLE				XE_REG(0x9134)	/* "_DISABLE" on Xe_LP */
 #define   XELP_EU_MASK				REG_GENMASK(7, 0)
+#define XELP_GT_SLICE_ENABLE			XE_REG(0x9138)
 #define XELP_GT_GEOMETRY_DSS_ENABLE		XE_REG(0x913c)
 
 #define GT_VEBOX_VDBOX_DISABLE			XE_REG(0x9140)