convert sysfs gpio usage to libgpod

This change removes the need to have ledFault objects defined in dbus.
It depends on consistent led fault pin name definition in device tree.

Tested by:
ipmitool raw 0x30 0x57 0x0 0x5 0x0 0x0 0xff 0xff 0xff 0xff 0xbe 0xef 0xde 0xad
ipmitool raw 0x30 0x57 0x0 0x0 0x0 0x0 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xaa
LEDs were turned on/off following the command on my WP system.

Clean up base on review feedback.

Signed-off-by: Zhikui Ren <zhikui.ren@intel.com>
Change-Id: I7cceae3ad343739e9f26374fe939f52f355c6442
1 file changed