The new helper returns index of the mathing string in an array.  We
would use it here.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>