drm/amd/display: Clean up errors in dce_clk_mgr.c

Fix the following errors reported by checkpatch:

ERROR: spaces required around that '?' (ctx:VxE)
Signed-off-by: Ran Sun <sunran001@208suo.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_clk_mgr.c

@@ -640,7 +640,7 @@ static void dce11_pplib_apply_display_requirements(
 	 * on power saving.
 	 *
 	 */
-	pp_display_cfg->min_dcfclock_khz = (context->stream_count > 4)?
+	pp_display_cfg->min_dcfclock_khz = (context->stream_count > 4) ?
 			pp_display_cfg->min_engine_clock_khz : 0;
 
 	pp_display_cfg->min_engine_clock_deep_sleep_khz