sata_dwc_460ex: disable compilation on ARM and ARM64

For now disable the compilation of the driver on ARM and ARM64. In the future
we will fix the DMA handling in that driver and re-enable compilation back.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>