This reverts commit 7d4defe2.

The commit was pointless, manically trembling in the dark for
a solution. The real fixes are:

commit 048c28c9
("gpio: make any OF dependent driver depend on OF_GPIO")
commit 2527ecc9
("gpio: Fix OF build problem on UM")
Reported-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>