No other fields in this class are prefixed with 'current' and it's in a class named State, so rename to make consistent.

Bug: b/126126820
Change-Id: I8eb26546141d1c11beb9acf57883d3d0835847b2
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/33354Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>