soundwire: Always wait for initialisation of unattached devices

Currently in sdw_slave_wait_for_init() the waiting can be skipped
if unattach_request is not set. Doing so was added in [1] likely
because the core used to do a complete() on the completion so
waiting in the case an unattach hadn't actually happened would
block for the full timeout. However patch [2] updated the core to
use complete_all() which means that the wait_for_completion() will
now simply return if the device is already attached skipping the
completion doesn't add much.

Additionally, unattach_request is only set if the host initiates
a bus reset. However, the host doing a bus reset is not the only
reason a device may be unattached from the bus. Other options
could include the driver probing before the device enumerates, a
sync-loss, or the device itself powering down.

Removing the skip using unattached_request, doesn't cost much in
terms of efficiency and allows the sdw_slave_wait_for_init() helper
to be used outside of runtime resume.

[1] b2bd75f806 ("soundwire: sdw_slave: track unattach_request to handle all init sequences")
[2] c40d6b3249 ("soundwire: fix enumeration completion")

Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20260608102714.2503120-2-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/soundwire/bus.c

@@ -1386,9 +1386,6 @@ int sdw_slave_wait_for_init(struct sdw_slave *slave, int timeout_ms)
 {
 	unsigned long time;
 
-	if (!slave->unattach_request)
-		return 0;
-
 	time = wait_for_completion_timeout(&slave->initialization_complete,
 					   msecs_to_jiffies(timeout_ms));
 	if (!time) {