bebob: often fail to take bootloader to run runtime firmware

[takaswie]

Reported in #21 and https://forum.manjaro.org/t/firewire-m-audio-410-driver-wont-load-firmware/51165.

With recent Linux kernel, snd-bebob often fail to take bootloader to run runtime firmware.

$ echo 1 > /sys/module/firewire_ohci/parameters/debug
(connect the device to IEEE 1394 bus and autoload snd-bebob)
$ journalctl -n 10
...
[12748.022203] firewire_ohci 0000:02:00.0: AT spd 2 tl 09, ffc1 -> ffc0, ack_pending , BR req, ffffc8020020 8,0
[12748.022305] firewire_ohci 0000:02:00.0: AR spd 0 tl 09, ffc0 -> ffc1, ack_complete, BR resp 8,31
[12748.022366] firewire_ohci 0000:02:00.0: AT spd 2 tl 0a, ffc1 -> ffc0, ack_pending , BW req, ffffc8021000 c,0
[12748.022482] firewire_ohci 0000:02:00.0: AR spd 0 tl 0a, ffc0 -> ffc1, ack_complete, W resp
[12748.022523] firewire_core 0000:02:00.0: created device fw1: GUID 000d6c01100af510, S400
...
$ cat /sys/bus/firewire/devices/fw1.0/model_name
FW Bootloader

The cause is not cleared yet.

[takaswie]

I filed this issue in bugzilla.kernel.org as a regression. https://bugzilla.kernel.org/show_bug.cgi?id=201021

[takaswie]

A fix was applied to sound subtree. https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git/commit/?id=493626f2d87a74e6dbea1686499ed6e7e600484e

This is going to be pulled to v4.20 kernel.