drm/amd/display: remove unused average_render_time_in_us and i variables

clang with W=1 reports
drivers/gpu/drm/amd/amdgpu/../display/modules/freesync/freesync.c:1132:15: error: variable
  'average_render_time_in_us' set but not used [-Werror,-Wunused-but-set-variable]
        unsigned int average_render_time_in_us = 0;
                     ^
This variable is not used so remove it, which caused i to be unused so remove that as well.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/modules/freesync/freesync.c

@@ -1129,7 +1129,6 @@ void mod_freesync_handle_preflip(struct mod_freesync *mod_freesync,
 {
 	struct core_freesync *core_freesync = NULL;
 	unsigned int last_render_time_in_us = 0;
-	unsigned int average_render_time_in_us = 0;
 
 	if (mod_freesync == NULL)
 		return;
@@ -1138,7 +1137,6 @@ void mod_freesync_handle_preflip(struct mod_freesync *mod_freesync,
 
 	if (in_out_vrr->supported &&
 			in_out_vrr->state == VRR_STATE_ACTIVE_VARIABLE) {
-		unsigned int i = 0;
 		unsigned int oldest_index = plane->time.index + 1;
 
 		if (oldest_index >= DC_PLANE_UPDATE_TIMES_MAX)
@@ -1147,18 +1145,6 @@ void mod_freesync_handle_preflip(struct mod_freesync *mod_freesync,
 		last_render_time_in_us = curr_time_stamp_in_us -
 				plane->time.prev_update_time_in_us;
 
-		/* Sum off all entries except oldest one */
-		for (i = 0; i < DC_PLANE_UPDATE_TIMES_MAX; i++) {
-			average_render_time_in_us +=
-					plane->time.time_elapsed_in_us[i];
-		}
-		average_render_time_in_us -=
-				plane->time.time_elapsed_in_us[oldest_index];
-
-		/* Add render time for current flip */
-		average_render_time_in_us += last_render_time_in_us;
-		average_render_time_in_us /= DC_PLANE_UPDATE_TIMES_MAX;
-
 		if (in_out_vrr->btr.btr_enabled) {
 			apply_below_the_range(core_freesync,
 					stream,