ALSA: wavefront: Proper check of get_user() error

commit a34ae6c0

 upstream.

The antient ISA wavefront driver reads its sample patch data (uploaded
over an ioctl) via __get_user() with no good reason; likely just for
some performance optimizations in the past.  Let's change this to the
standard get_user() and the error check for handling the fault case
properly.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220510103626.16635-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>