UPSTREAM: regulator: core: Move registration of regulator device

UPSTREAM: regulator: core: Move registration of regulator device

The public functions to acquire a regulator, such as regulator_get(),
internally look-up the regulator from the list of regulators that have
been registered with the regulator device class. The registration of
a new regulator with the regulator device class happens before the
regulator has been completely setup. Therefore, it is possible that
the regulator could be acquired before it has been setup successfully.
To avoid this move the device registration of the regulator to the end
of the regulator setup and update the error exit path accordingly.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit c438b9d017362b65f6b1a9e54f7f35e7f873dc7c)

Change-Id: I9b33820c1ea748fdf5ccfb8949775b753af4a848
Signed-off-by: David Wu <david.wu@rock-chips.com>