regulator: max597x: Don't return uninitialized variable in .probe

Remove the code checking and returning uninitialized variable.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Link: https://lore.kernel.org/r/20220714101212.502824-1-axel.lin@ingics.com


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