Lax specification of register values' effects

[jonnew]

The behavior of Running and Reset global acquisition registers is specified here:

ONI/source/hw-spec/controller.rst

Line 322 in 3b2a0e2

- ``Running``: Set to > 0 to run the system clock and produce data. Set to 0 to

Rather than specifying precise values and reserved bits, which is much more forgiving for future modifications that mantain backwards compatibility, values are specified into two groups:

value == 0 -> Behavior A
value /= 0  -> Behavior B

I don't see a good reason to do this, at least in this case, rather than specifying e.g.

value == 0x0 -> Behavior A
value == 0x1 -> Behavior B
else -> Reserved

There may be other instances of this type of thing in the spec that we should consider.

[jonnew]

This has started to be addressed in various PRs but we need to do a look over to make sure its uniform across version 2.0.