GATT_CancelConnect() function

* Function GATT_CancelConnect * Description This function terminate the connection initiation to a remote * device on GATT channel. * Parameters gatt_if: client interface. If 0 used as unconditionally disconnect, * typically used for direct connection cancellation. * bd_addr: peer device address. * is_direct: is a direct connection or a background auto connection * Returns TRUE if connection started; FALSE if connection start failure.