radv: copy indirect lowering settings from radeonsi

It looks the original indirect mask was probably copied from
ANV.

Sascha Willems demo results:

tessellation ~4000 -> ~4200 fps

V2: continue lowering local indirects due to llvm deficiencies.

(cherry picked from commit 087e010b)
[Bas Nieuwenhuizen: patch is a backport for 17.2 of the cherry-pick above]