smartreflex-class1p5: custom voltage: fix unusable voltage corridor for control fuses that are used for more than one OPP
Previously, when using volt_margins to differentiate voltages for different OPPs
using the same control fuse, the usage of the full voltage spectrum was barred.
This patch fixes the issue.

Signed-off-by: Boy Petersen <boypetersen@gmail.com>
Signed-off-by: Dan Trifan <jimsth@gmail.com>