staging: olpc_dcon: Augment TODO file with GPIO work item

To make sure that this driver does not leave staging before it
is properly converted to use the new GPIO descriptor API,
augment the TODO file with this work item.

Cc: Andres Salomon <dilinger@queued.net>
Cc: Jens Frederich <jfrederich@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/olpc_dcon/TODO

 TODO:
 	- see if vx855 gpio API can be made similar enough to cs5535 so we can
 	  share more code
+	- convert all uses of the old GPIO API from <linux/gpio.h> to the
+	  GPIO descriptor API in <linux/gpio/consumer.h> and look up GPIO
+	  lines from device tree, ACPI or board files, board files should
+	  use <linux/gpio/machine.h>
 	- allow simultaneous XO-1 and XO-1.5 support
 
 Please send patches to Greg Kroah-Hartman <greg@kroah.com> and