glsl: Pass ctx->Const.NativeIntegers to do_common_optimization().

glsl: Pass ctx->Const.NativeIntegers to do_common_optimization().

The next few patches will introduce an optimization that only works when
integers are not represented as floating point values.

v2: Re-word-wrap a line, as requested by Ian Romanick.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>