sound: oss: msnd_pinnacle: avoid interruptible_sleep_on_timeout

We want to remove all sleep_on variants from the kernel because they are
racy. In case of the pinnacle driver, we can replace
interruptible_sleep_on_timeout with wait_event_interruptible_timeout
by changing the meaning of a few flags used in the driver so they
are cleared at wakeup time, which is a somewhat more appropriate
way to do the same, although probably still racy.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>