Optimize BindingNormalizedNodeCodecRegistry representation checks

Optimize BindingNormalizedNodeCodecRegistry representation checks

isBindingRepresentable() is a hot method, which performs a few
type checks. This patch folds those checks into a single return,
inverting the logic (which is negated anyway at the sole caller).
This cuts the amount of byte code to half, thus aiding inlining.

Futhermore we take advantage of ValueNode covering two cases we
explicitly test for, reducing the number of checks performed.

Finally we reorder the checks to improve their efficiency by
tackling most-common constructs first.

Change-Id: I556d1098a9d7dd043b2f8d756c2388f339f6b8ec
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>