anv: Replace ::disable_scissor with ::use_rectlists

anv: Replace ::disable_scissor with ::use_rectlists

Meta currently uses screenspace RECTLIST primitives that lie within
the framebuffer rectangle. Since this behavior shouldn't change in the
future, disable the scissor operation whenever rectlists are used.

Signed-off-by: Nanley Chery <nanley.g.chery@intel.com>
Reviewed-by: Kristian Høgsberg Kristensen <kristian.h.kristensen@intel.com>