meta-fii: meta-kudo: Use GPIO line names instead of number

Replaces hard-coded GPIO throughout the Kudo layer with a reference
to its line name from DTS.

The process to dynamically obtain the GPIO number for Get is added
to kudo-lib.sh,
 1. Use `gpiofind <Line Name>` to obtain gpiochip# and pin#
 2. If the gpiochip# exceeds the number of GPIO banks of Nuvoton,
    then it is an I/O Expander.
    a. Use `gpiodetect` and extract the I2C bus-addr
    b. Obtain GPIO base value from sysfs using bus-addr
    c. The GPIO number is then the (base + pin#)
 3. If the gpiochip# is within Nuvoton GPIO banks, then calculate
    the GPIO number as ((gpiochip#)*32 + pin#)
Then the GPIO number can be used in the export to obtain the value.

Tested with Nuvoton:
 - Can read/set Nuvoton GPIO with defined line names
 - Can read/set GPIO from I/O Expanders with defined line names

Signed-off-by: Charles Boyer <Charles.Boyer@fii-usa.com>
Change-Id: I651c0707a8bbc170d3c5a5fc261e5f9c62453e9f