bluetooth: tester: Convert GATT service to new BTP API

This makes GATT service to use new BTP command handlers API.

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>

tests/bluetooth/tester/src/btp/btp_gatt.h

@@ -332,6 +332,16 @@ struct btp_gatt_eatt_connect_cmd {
 } __packed;
 
 #define BTP_GATT_READ_MULTIPLE_VAR		0x20
+struct btp_gatt_read_multiple_var_cmd {
+	bt_addr_le_t address;
+	uint8_t handles_count;
+	uint16_t handles[];
+} __packed;
+struct btp_gatt_read_multiple_var_rp {
+	uint8_t att_response;
+	uint16_t data_length;
+	uint8_t data[];
+} __packed;
 
 #define BTP_GATT_NOTIFY_MULTIPLE		0x21
 struct btp_gatt_cfg_notify_mult_cmd {

tests/bluetooth/tester/src/btp/bttester.h

@@ -44,8 +44,6 @@ void tester_register_command_handlers(uint8_t service,
 
 uint8_t tester_init_gatt(void);
 uint8_t tester_unregister_gatt(void);
-void tester_handle_gatt(uint8_t opcode, uint8_t index, uint8_t *data,
-			uint16_t len);
 
 uint8_t tester_init_l2cap(void);
 uint8_t tester_unregister_l2cap(void);