Add GPIO pin description

Added functionality to read gpio pin code description from
gpio_desc.json file stored in /usr/share/ipmi-providers/.
This file is platform specific and can be overwritten for
different platforms. This gpio pin description will be
requested by lcd debug card for displaying in screen.

Tested: verified with lcd debug card screen.

Change-Id: I32275a5d218cbfdd20cd919768688ab6cc67b091
Signed-off-by: Vijay Khemka <vijaykhemka@fb.com>
4 files changed