libtraceevent: Remove unneeded semicolon

Fixes coccicheck warning:

 tools/lib/traceevent/kbuffer-parse.c:441:2-3: Unneeded semicolon
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NZou Wei <zou_wei@huawei.com>
Acked-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/1588065121-71236-1-git-send-email-zou_wei@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/traceevent/kbuffer-parse.c

@@ -438,7 +438,7 @@ void *kbuffer_translate_data(int swap, void *data, unsigned int *size)
 	case KBUFFER_TYPE_TIME_EXTEND:
 	case KBUFFER_TYPE_TIME_STAMP:
 		return NULL;
-	};
+	}
 
 	*size = length;