net: pch_gbe: Propagate error from devm_gpio_request_one()

net: pch_gbe: Propagate error from devm_gpio_request_one()

[ Upstream commit 9e3617a7b84512bf96c04f9cf82d1a7257d33794 ]

If GPIO controller is not available yet we need to defer
the probe of GBE until provider will become available.

While here, drop GPIOF_EXPORT because it's deprecated and
may not be available.

Fixes: f1a26fdf5944 ("pch_gbe: Add MinnowBoard support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Flavio Suligoi <f.suligoi@asem.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>