dt-bindings: net: nfc: s3fwrn5: Support a UART interface

Since S3FWRN82 NFC Chip, The UART interface can be used.
S3FWRN82 supports I2C and UART interface.

Signed-off-by: Bongsu Jeon <bongsu.jeon@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>