[`ring`]: `getMinimumGap` returns incoherent values

[Pro7ech]

The following piece of code of the function

lattigo/core/rlwe/ring_packing.go

Line 834 in 1d70f2c

func getMinimumGap(list []int) (gap, logGap int, err error) {

is incoherent:

for gap&1 == 0 {
	logGap++  // gap.trailing_zeros()
	gap >>= 1 // gap >> gap.trailing_zeros()
}

but x.trailing_zeros() != (x >> x.trailing_zeros()).bit_length().

edit: the naming logGap is misleading, but the returned value is what is expected by the other methods that call it.