drm/amd/display: Pass non-null to dcn20_validate_apply_pipe_split_flags

[WHAT & HOW]
"dcn20_validate_apply_pipe_split_flags" dereferences merge, and thus it
cannot be a null pointer. Let's pass a valid pointer to avoid null
dereference.

This fixes 2 FORWARD_NULL issues reported by Coverity.
Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/resource/dcn20/dcn20_resource.c

@@ -2040,6 +2040,7 @@ bool dcn20_fast_validate_bw(
 {
 	bool out = false;
 	int split[MAX_PIPES] = { 0 };
+	bool merge[MAX_PIPES] = { false };
 	int pipe_cnt, i, pipe_idx, vlevel;
 
 	ASSERT(pipes);
@@ -2064,7 +2065,7 @@ bool dcn20_fast_validate_bw(
 	if (vlevel > context->bw_ctx.dml.soc.num_states)
 		goto validate_fail;
 
-	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, NULL);
+	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, merge);
 
 	/*initialize pipe_just_split_from to invalid idx*/
 	for (i = 0; i < MAX_PIPES; i++)

drivers/gpu/drm/amd/display/dc/resource/dcn21/dcn21_resource.c

@@ -774,6 +774,7 @@ bool dcn21_fast_validate_bw(struct dc *dc,
 {
 	bool out = false;
 	int split[MAX_PIPES] = { 0 };
+	bool merge[MAX_PIPES] = { false };
 	int pipe_cnt, i, pipe_idx, vlevel;
 
 	ASSERT(pipes);
@@ -816,7 +817,7 @@ bool dcn21_fast_validate_bw(struct dc *dc,
 			goto validate_fail;
 	}
 
-	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, NULL);
+	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, merge);
 
 	for (i = 0, pipe_idx = 0; i < dc->res_pool->pipe_count; i++) {
 		struct pipe_ctx *pipe = &context->res_ctx.pipe_ctx[i];