What's the point of that?
I mean... both springs load on the same piece so... they share tension so it's the same than a single spring with different tension. Always the softer one will "unload" and the tension on the pads will be just the same. The only thing that will vary the friction will be the mu coeficient between disc and pad.
You need something a litte bit more complex to achieve an adjustable "bi-slipper"
so both end can use its own tension.