r600/sb: do not convert if-blocks that contain indirect array access

If an array is accessed within an if block, then currently it is not known
whether the value in the address register is involved in the evaluation of the
if condition, and converting the if condition may actually result in
out-of-bounds array access. Consequently, if blocks that contain indirect array
access should not be converted.

Fixes piglits on r600/BARTS:
spec/glsl-1.10/execution/variable-indexing/
  vs-output-array-float-index-wr
  vs-output-array-vec3-index-wr
  vs-output-array-vec4-index-wr

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104143



Signed-off-by: Gert Wollny <gw.fossdev@gmail.com>
Cc: <mesa-stable@lists.freedesktop.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(cherry picked from commit 6c268ea7)