NFC: nxp-nci: Convert to use GPIO descriptor

Since we got rid of platform data, the driver may use
GPIO descriptor directly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>