Staging: android: add timed_gpio driver

driver for GPIOs that turn back off after a delay

From: Mike Lockwood <lockwood@android.com>
Signed-off-by: Brian Swetland <swetland@google.com>
Cc: Robert Love <rlove@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>