dmaengine: dw: Replace 'objs' by 'y'

`-objs` is fitted for building host programs, change to `-y`,
more straightforward for device drivers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200526182416.52805-2-andriy.shevchenko@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>