This commit adds sysfs files to enable or disable the LEDs on the
X52 Pro joystick. This also fixes a minor bug with the brightness
API which was always complaining not-supported.
This still has a bug in that the text is not written correctly. It
shows up as garbage. For now, I'm committing it so that I can work
on it later after the brightness configuration is set up.
Also add the commands header file.
This is pretty much bare bones code to get a basic sysfs filesystem
in place. It has only code to create sysfs files for the 3 MFD lines.
Right now, this needs to be enabled by unplugging the joystick,
insmod'ing the x52joy.ko module, rmmod'ing the usbhid module and
replugging the joystick. We don't yet have a /dev/input/ interface
and there's no interrupt message handling yet.