pinctrl: lpc18xx: create pin cap lookup helper
pinctrl: lpc18xx: create pin cap lookup helper

Both pconf_get_pin and pconf_set_pin needs to lookup pin cap based
on the pin number. Create a common helper function that both
functions can use that also handles the case where no pin number is
found in the pins array.

This also fixes a small bug in pconf_get_pin where pconf_get_i2c0
would use the pins array index rather than the pin number.

Signed-off-by: Joachim Eastwood <6f54d78a4cd927eb19dd17c34117bfc80f7abcf7@gmail.com>
Signed-off-by: Linus Walleij <9cd9d802d23c0ed5e224beabf4ae4a5c478746ef@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs