Allow some Bignum primitives to inline (#20361)
As explained in #20361, I'm transferring some constant folding rules from Natural/Integer primitives to BigNat# primitives to allow the former to be inlined without breaking constant folding.
In this batch we remove NOINLINE on Natural's:
- Eq/Ne/Gt/Lt/Ge/Le predicates
- compare
- negate
- signum
- naturalToWordClamp#
- naturalTo/FromAddr#
- naturalToMutableByteArray#, naturalFromByteArray#