Add support for libgpiod v2+ API

[mcuee]

Reference:

• Add support for libgpiod v2+ API #1725 (comment)

libgpiod in version 2 or above introduced an API change which results in compile error with the current code.

[mcuee]

I can confirm the above statement.

• Add support for libgpiod v2+ API #1725 (comment)

PR #1725 tries to address the issue but it is not working yet. Building is okay but it does not seem to work.

• Add support for libgpiod v2+ API #1725 (comment)

[mcuee]

PR #1725 is now working with the libgpiod v2+ API change. There is still an issue with sysfs fall back which is captured in Issue #1751.

• linuxgpio sysfs fallback improvement to deal with shifted GPIO numbering in new kernel version #1751