regulator: cpr3-hmss-regulator: correct handling of LowSVS voltage corner

Set the fused LowSVS corner open-loop voltage to be equal to the
post-adjustment fused SVS corner open-loop voltage.  This ensures
that open-loop voltage interpolation is not incorrectly disabled
in the case that a negative SVS corner open-loop adjustment is
defined in the device tree.

Change-Id: Idd1b37cabfd85d32c687d4aa18fb197765cec710
Signed-off-by: David Collins <collinsd@codeaurora.org>