soundwire: intel_init: add kernel module parameter to filter out links

soundwire: intel_init: add kernel module parameter to filter out links

The hardware and ACPI info may report the presence of links that are
not physically enabled (e.g. due to pin-muxing or hardware reworks),
which in turn can result in errors being thrown. This shouldn't be the
case for production devices but will happen a lot on development
devices - even more so when they expose a connector.

Even when the ACPI information is correct, it's useful to be able to
only enable the links that need attention - mostly to filter out
dynamic debug messages.

Add a module parameter to filter out such links, e.g. adding the
following config to a file in /etc/modprobe.d will select the second
and third links only.

options soundwire_intel_init sdw_link_mask=0x6

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-16-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>