PM: sleep: Rearrange suspend/resume error handling in the core

Notice that device_suspend_noirq(), device_suspend_late() and
device_suspend() all set async_error on errors, so they don't really
need to return a value.  Accordingly, make them all void and use
async_error in their callers instead of their return values.

Moreover, since async_error is updated concurrently without locking
during asynchronous suspend and resume processing, use READ_ONCE() and
WRITE_ONCE() for accessing it in those places to ensure that all of the
accesses will be carried out as expected.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Link: https://patch.msgid.link/6198088.lOV4Wx5bFT@rjwysocki.net