The sampling routine no longer requires a sampler parameter, since all
data is treated as state instead.

Bug: b/151957215
Change-Id: I1917bf78ef18f6726ed6c87525f0bc42356d5c19
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/42589Tested-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>