iwlwifi: use DEFINE_MUTEX() for mutex lock

mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210802172232.2a583d006739.Ia782c08525397b6430b1c877a870d688a7f3f494@changeidSigned-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/iwl-drv.c

@@ -78,7 +78,7 @@ enum {
 };
 
 /* Protects the table contents, i.e. the ops pointer & drv list */
-static struct mutex iwlwifi_opmode_table_mtx;
+static DEFINE_MUTEX(iwlwifi_opmode_table_mtx);
 static struct iwlwifi_opmode_table {
 	const char *name;			/* name: iwldvm, iwlmvm, etc */
 	const struct iwl_op_mode_ops *ops;	/* pointer to op_mode ops */
@@ -1754,8 +1754,6 @@ static int __init iwl_drv_init(void)
 {
 	int i, err;
 
-	mutex_init(&iwlwifi_opmode_table_mtx);
-
 	for (i = 0; i < ARRAY_SIZE(iwlwifi_opmode_table); i++)
 		INIT_LIST_HEAD(&iwlwifi_opmode_table[i].drv);