airo: Replace in_atomic() usage.

issuecommand() is using in_atomic() to decide if it is safe to invoke
schedule() while waiting for the command to be accepted.

Usage of in_atomic() for this is only half correct as it can not detect all
condition where it is not allowed to schedule(). Also Linus clearly
requested that code which changes behaviour depending on context should
either be seperated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

Add an may_sleep argument to issuecommand() indicating when it is save to
sleep and change schedule() to cond_resched() because it's pointless to
invoke schedule() if there is no request to reschedule.

Pass the may_sleep condition through the various call chains leading to
issuecommand().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: linux-wireless@vger.kernel.org
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201101211536.2966644-5-bigeasy@linutronix.de