drm/amdgpu/display: move link_bandwidth_kbps under CONFIG_DRM_AMD_DC_DCN

It's only used when CONFIG_DRM_AMD_DC_DCN is set.  Fixes and set but
not used warning.
Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -5120,9 +5120,8 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 	int preferred_refresh = 0;
 #if defined(CONFIG_DRM_AMD_DC_DCN)
 	struct dsc_dec_dpcd_caps dsc_caps;
-#endif
 	uint32_t link_bandwidth_kbps;
-
+#endif
 	struct dc_sink *sink = NULL;
 	if (aconnector == NULL) {
 		DRM_ERROR("aconnector is NULL!\n");
@@ -5204,11 +5203,9 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 				      aconnector->dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.raw,
 				      aconnector->dc_link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.raw,
 				      &dsc_caps);
-#endif
 		link_bandwidth_kbps = dc_link_bandwidth_kbps(aconnector->dc_link,
 							     dc_link_get_link_cap(aconnector->dc_link));
 
-#if defined(CONFIG_DRM_AMD_DC_DCN)
 		if (aconnector->dsc_settings.dsc_force_enable != DSC_CLK_FORCE_DISABLE && dsc_caps.is_dsc_supported) {
 			/* Set DSC policy according to dsc_clock_en */
 			dc_dsc_policy_set_enable_dsc_when_not_needed(