drm/amd/display: reduce scope for local var

[Why]
No reason to have uninitialized var at top of function

[How]
Move it to minimum scope where it's actuallty used
Signed-off-by: NAric Cyr <aric.cyr@amd.com>
Acked-by: NBindu Ramamurthy <bindu.r@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -2348,7 +2348,6 @@ static void commit_planes_do_stream_update(struct dc *dc,
 		struct dc_state *context)
 {
 	int j;
-	bool should_program_abm;
 
 	// Stream updates
 	for (j = 0; j < dc->res_pool->pipe_count; j++) {
@@ -2424,7 +2423,7 @@ static void commit_planes_do_stream_update(struct dc *dc,
 			}
 
 			if (stream_update->abm_level && pipe_ctx->stream_res.abm) {
-				should_program_abm = true;
+				bool should_program_abm = true;
 
 				// if otg funcs defined check if blanked before programming
 				if (pipe_ctx->stream_res.tg->funcs->is_blanked)