drm/amd/display: Update 709 gamma to 2.222 as stated in the standerd

[WHY]
    Previously driver use gamma 2.2 for 709 color space,
    but the standard is to use gamma of 2.222

[HOW]
    Change it gamma to 2.222
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Nawwar Ali <nawwar.ali@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/modules/color/color_gamma.c

@@ -61,7 +61,7 @@ static const int32_t numerator01[] = { 31308,   180000, 0,  0,  0};
 static const int32_t numerator02[] = { 12920,   4500,   0,  0,  0};
 static const int32_t numerator03[] = { 55,      99,     0,  0,  0};
 static const int32_t numerator04[] = { 55,      99,     0,  0,  0};
-static const int32_t numerator05[] = { 2400,    2200,   2200, 2400, 2600};
+static const int32_t numerator05[] = { 2400,    2222,   2200, 2400, 2600};
 
 /* one-time setup of X points */
 void setup_x_points_distribution(void)