drm/komeda: Clean warning 'komeda_component_add' might be a candidate for 'gnu_printf'

komeda/komeda_pipeline.c: In function 'komeda_component_add':
komeda/komeda_pipeline.c:212:3: warning: function 'komeda_component_add' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
   vsnprintf(c->name, sizeof(c->name), name_fmt, args);
   ^~~~~~~~~
Signed-off-by: james qian wang (Arm Technology China) <james.qian.wang@arm.com>
Reviewed-by: Ayan Kumar Halder <ayan.halder@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190813110759.10425-1-james.qian.wang@arm.com

drivers/gpu/drm/arm/display/komeda/komeda_pipeline.h

@@ -480,6 +480,7 @@ void komeda_pipeline_dump_register(struct komeda_pipeline *pipe,
 				   struct seq_file *sf);
 
 /* component APIs */
+extern __printf(10, 11)
 struct komeda_component *
 komeda_component_add(struct komeda_pipeline *pipe,
 		     size_t comp_sz, u32 id, u32 hw_id,