st/mesa: Avoid setting EmitNoIndirectSampler on iris; iris: Disable GLSL IR loop unrolling
Patch 1 changes st/mesa's EmitNoIndirectSampler settings so that iris can handle indirect sampler array access in non-core contexts. Patch 2 disables GLSL IR loop unrolling in iris (and requires the first to avoid a Piglit regression, where the linker sees an indirect and panics, when ultimately NIR will unroll it later).