drm/i915: make a handful of read-only arrays static const

Don't populate the read-only arrays on the stack but instead make
them static const and signed 8 bit ints. Also makes the object code a
little smaller.  Reformat the statements to clear up checkpatch warning.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220223120923.239867-1-colin.i.king@gmail.com

drivers/gpu/drm/i915/display/intel_vdsc.c

@@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
 {
 	int bpc = vdsc_cfg->bits_per_component;
 	int bpp = vdsc_cfg->bits_per_pixel >> 4;
-	int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
-	int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
-	int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
-	int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
+	static const s8 ofs_und6[] = {
+		0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
+	};
+	static const s8 ofs_und8[] = {
+		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+	};
+	static const s8 ofs_und12[] = {
+		2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+	};
+	static const s8 ofs_und15[] = {
+		10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
+	};
 	int qp_bpc_modifier = (bpc - 8) * 2;
 	u32 res, buf_i, bpp_i;