ALSA: scarlett2: Default mixer driver to enabled

[ Upstream commit bc83058f ]

Early versions of this mixer driver did not work on all hardware, so
out of caution the driver was disabled by default and had to be
explicitly enabled with device_setup=1.

Since commit 764fa6e6 ("ALSA: usb-audio: scarlett2: Fix device
hang with ehci-pci") no more problems of this nature have been
reported. Therefore, enable the driver by default but provide a new
device_setup option to disable the driver in case that is needed.

- device_setup value of 0 now means "enable" rather than "disable".
- device_setup value of 1 is now ignored.
- device_setup value of 4 now means "disable".

Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/89600a35b40307f2766578ad1ca2f21801286b58.1694705811.git.g@b4.vu


Signed-off-by: Takashi Iwai <tiwai@suse.de>
Stable-dep-of: b61a3aca ("ALSA: scarlett2: Add Focusrite Clarett+ 2Pre and 4Pre support")
Signed-off-by: Sasha Levin <sashal@kernel.org>