Bluetooth: hci_sync: Correct hci_set_event_mask_page_2_sync() event mask

Event HCI_Truncated_Page_Complete should belong to central
and HCI_Peripheral_Page_Response_Timeout should belong to
peripheral, but hci_set_event_mask_page_2_sync() take these
two events for wrong roles, so correct it by this change.

Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>