regulator: of: fix a NULL vs IS_ERR() check in of_regulator_bulk_get_all()

The regulator_get() function never returns NULL. It returns error pointers.

Fixes: 27b9ecc7 ("regulator: Add of_regulator_bulk_get_all")
Signed-off-by: Peng Wu <wupeng58@huawei.com>
Link: https://lore.kernel.org/r/20221122082242.82937-1-wupeng58@huawei.com


Signed-off-by: Mark Brown <broonie@kernel.org>