mt7615: mcu: use standard signature for mt7615_mcu_msg_send

Use mt76 common signature for mt7615_mcu_msg_send. Move skb allocation
in mt7615_mcu_msg_send and remove duplicated code. Remove
__mt7615_mcu_set_wtbl and __mt7615_mcu_set_sta_rec since now are used
just to send mcu msgs.  This is a preliminary patch for mt7615-mt7603 mcu
code unification
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7615/mcu.h

@@ -201,6 +201,13 @@ enum {
 	WTBL_RESET_ALL
 };
 
+struct wtbl_req_hdr {
+	u8 wlan_idx;
+	u8 operation;
+	__le16 tlv_num;
+	u8 rsv[4];
+} __packed;
+
 struct wtbl_generic {
 	__le16 tag;
 	__le16 len;
@@ -366,7 +373,8 @@ struct wtbl_raw {
 	__le32 val;
 } __packed;
 
-#define MT7615_WTBL_UPDATE_MAX_SIZE (sizeof(struct wtbl_generic) + \
+#define MT7615_WTBL_UPDATE_MAX_SIZE (sizeof(struct wtbl_req_hdr) + \
+				     sizeof(struct wtbl_generic) + \
 				     sizeof(struct wtbl_rx) + \
 				     sizeof(struct wtbl_ht) + \
 				     sizeof(struct wtbl_vht) + \
@@ -400,6 +408,15 @@ enum {
 	WTBL_MAX_NUM
 };
 
+struct sta_req_hdr {
+	u8 bss_idx;
+	u8 wlan_idx;
+	__le16 tlv_num;
+	u8 is_tlv_append;
+	u8 muar_idx;
+	u8 rsv[2];
+} __packed;
+
 struct sta_rec_basic {
 	__le16 tag;
 	__le16 len;