Enlarge zram max size

[chn-lee-yumi]

Nowadays mobile phones' RAM are larger and larger, on some phones its default zram is larger than the maximum value in this app (such as Mi 6X, its RAM is 4GB and default zram is 2252MB). The value 2048 is not enough, so I enlarge it to 4096, and change the offset from 10 to 16.