ACPI / EC: Fix a memory leak issue in acpi_ec_query()

When query handler is not found, "result" is actually stil 0, and
"struct acpi_ec_query" is not NULL, so the deletion code of
"struct acpi_ec_query" at the end of the function cannot be invoked.
As a consequence, memory leak can be observed.

The issue is introduced by this commit:
  Commit: 02b771b64b73226052d6e731a0987db3b47281e9
  Subject: ACPI / EC: Fix an issue caused by the serialized _Qxx

This patch fixes such memory leakage.

Fixes: 02b771b64b73 (ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations)
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/ec.c

@@ -1044,8 +1044,10 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
 		goto err_exit;
 
 	mutex_lock(&ec->mutex);
+	result = -ENODATA;
 	list_for_each_entry(handler, &ec->list, node) {
 		if (value == handler->query_bit) {
+			result = 0;
 			q->handler = acpi_ec_get_query_handler(handler);
 			ec_dbg_evt("Query(0x%02x) scheduled",
 				   q->handler->query_bit);