staging: wilc1000: use kmalloc(sizeof(*mgmt_tx)...) in mgmt_tx()

Fix below checkpatch issue found in mgmt_tx()

Prefer kmalloc(sizeof(*mgmt_tx)...) over kmalloc(sizeof(struct
p2p_mgmt_data)...)
Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wilc1000/wilc_wfi_cfgoperations.c

@@ -1622,7 +1622,7 @@ static int mgmt_tx(struct wiphy *wiphy,
 	if (!ieee80211_is_mgmt(mgmt->frame_control))
 		goto out;
 
-	mgmt_tx = kmalloc(sizeof(struct p2p_mgmt_data), GFP_KERNEL);
+	mgmt_tx = kmalloc(sizeof(*mgmt_tx), GFP_KERNEL);
 	if (!mgmt_tx) {
 		ret = -ENOMEM;
 		goto out;