pinctrl: Remove unsafe __refdata

A pin controller's pin definitions are used both during pinctrl_register()
and pinctrl_unregister(). The latter happens outside of __init/__devinit
time, and hence it is unsafe to mark the pin array as __refdata.

Acked-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>