We now deal with NaN and Inf results from the cube map face projection
in the SamplerCore:address() method by clamping to the [0.0, 1.0) range,
so we can just let the pathological division-by-zero cases happen and
not spend more cycles on preventing it.

Bug: b/169802633
Change-Id: I329420415f6e3b913d912b357758f92f8e0ee7f4
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/48828
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>