i2c: pca-platform: add devicetree awareness

Allow devices that use this driver to be registered via a
devicetree.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
[wsa: fixed leakage when registering GPIO failed]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
1 file changed