ALSA: usb-audio: disable implicit feedback sync for Behringer UFX1204 and UFX1604

Behringer UFX1204 and UFX1604 have Synchronous endpoints to which
current ALSA code applies implicit feedback sync as if they were
Asynchronous endpoints. This breaks UAC compliance and is unneeded.

The commit 5e35dc03 and subsequent
1a15718b were meant to clear up noise.

Unfortunately, noise persisted for those using higher sample rates and
this was only solved by commit d2e8f641

Since there are no more reports of noise, let's get rid of the
implicit-fb quirks breaking UAC compliance.

Signed-off-by: Geraldo Nascimento <geraldogabriel@gmail.com>
Link: https://lore.kernel.org/r/YVYSnoQ7nxLXT0Dq@geday


Signed-off-by: Takashi Iwai <tiwai@suse.de>