Change interface to GPIO access to allow configuration of exported name

[Rob Cordeau]

Hi,
I am working on a board that exports GPIOs in a format that is different
than what dio expects.  Currently it is hard coded in dio to access a gpio
at /sys/class/gpio/gpio# when the gpio is exported, but the board I am on
has it configured in the kernel to export, say, GPIO39 as
/sys/class/gpio/P3_1 for example.  There is no way the DIO code can control
this gpio unless I modify the kernel to export the gpio name to what DIO
expects.  Can DIO change to allow the name of the exported gpio to be
passed in?

Thanks,
Rob