Fix upgrade condition for equilibrium

[yarukishi]

The current upgrade conditions for the Equilibrium feat do not correctly handle the case where more than 50 pillars have been completed and the pillars are of nonuniform rank. In this case, Equilibrium will assume the value of the lowest-rank pillar, even when 50 pillars have been completed at a higher rank.

I tested various configurations and found that this patch behaves as expected.

Example save to test: equilibrium.txt