intel/vec4/gs: reset nr_pull_param if DUAL_INSTANCED compile failed.

If dual object compile fails (as seems to happen with virgl a
fair bit, and does piglit even have any tests for it?), we end up
not restarting the pull params, so we call
vec4_visitor::move_uniform_array_access_to_pull_constant
a second time and it runs over the ends of the alloc.

Fixes: tests/spec/glsl-1.50/execution/geometry/max-input-components.shader_test
running inside virgl on ivybridge.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: <mesa-stable@lists.freedesktop.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

src/intel/compiler/brw_vec4_gs_visitor.cpp

@@ -912,6 +912,7 @@ brw_compile_gs(const struct brw_compiler *compiler, void *log_data,
             memcpy(prog_data->base.base.param, param,
                    sizeof(gl_constant_value*) * param_count);
             prog_data->base.base.nr_params = param_count;
+            prog_data->base.base.nr_pull_params = 0;
             ralloc_free(param);
          }
       }