drm/amd/display: remove unused matching_stream_ptrs variable

clang with W=1 reports
drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link_enc_cfg.c:625:6: error:
  variable 'matching_stream_ptrs' set but not used [-Werror,-Wunused-but-set-variable]
        int matching_stream_ptrs = 0;
            ^
This variable is not used so remove it.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
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/dc/core/dc_link_enc_cfg.c

@@ -622,7 +622,6 @@ bool link_enc_cfg_validate(struct dc *dc, struct dc_state *state)
 	int i, j;
 	uint8_t valid_count = 0;
 	uint8_t dig_stream_count = 0;
-	int matching_stream_ptrs = 0;
 	int eng_ids_per_ep_id[MAX_PIPES] = {0};
 	int ep_ids_per_eng_id[MAX_PIPES] = {0};
 	int valid_bitmap = 0;
@@ -645,9 +644,7 @@ bool link_enc_cfg_validate(struct dc *dc, struct dc_state *state)
 		struct link_enc_assignment assignment = state->res_ctx.link_enc_cfg_ctx.link_enc_assignments[i];
 
 		if (assignment.valid) {
-			if (assignment.stream == state->streams[i])
-				matching_stream_ptrs++;
-			else
+			if (assignment.stream != state->streams[i])
 				valid_stream_ptrs = false;
 		}
 	}