Bluetooth: Pass store hint to mgmt_new_conn_param

The calling functions of mgmt_new_conn_param have more information about
the parameters, such as whether the kernel is tracking them or not. It
makes therefore sense to have them pass an initial store_hint value to
the mgmt_new_conn_param function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>