fireworks/bebob/oxfw: Check return value of snprintf()
oxfw: Fix failure to .probe

When assuming stream formation, AV/C inquire commands are used to get
supported sampling rates. This command returns 'NOT IMPLEMENTED' when
asked sampling rate is not supported.

So it should be better to ignore return values at assuming.
firewire-lib: Add sorting in-packets for full duplex streams with sync

In full duplex streams with synchronization, consistency of SYT field in
in-packets is important for out-packets. This commit add sorting in-packets
according to the value of dbc.