spef_extractor: remove some unused variables and scalarize some others (#55)
spef_extractor: remove some unused variables and scalarize some others (#55)

The minCap/maxCap variables were never really used.
The edgeCapFactor, capCounter and resCounter variables were lists with
always 1 element, so they can be scalarized.
efabless/openlane,efabless/openlane,efabless/openlane,efabless/openlane