gallium: remove uses_kill field from softpipe_shader

src/gallium/drivers/softpipe/sp_quad.c

                sp->depth_stencil->depth.enabled &&
                sp->framebuffer.zsbuf &&
                !sp->depth_stencil->alpha.enabled &&
-               !sp->fs->uses_kill &&
+               !sp->fs->info.uses_kill &&
                !sp->fs->info.writes_z;
 
    /* build up the pipeline in reverse order... */

src/gallium/drivers/softpipe/sp_state.h

 
    struct tgsi_shader_info info;
 
-   boolean uses_kill;
-
    void (*prepare)( const struct sp_fragment_shader *shader,
 		    struct tgsi_exec_machine *machine,
 		    struct tgsi_sampler *samplers);

src/gallium/drivers/softpipe/sp_state_fs.c

    /* get/save the summary info for this shader */
    tgsi_scan_shader(templ->tokens, &state->info);
 
-   /* convenience field */
-   state->uses_kill = (state->info.opcode_count[TGSI_OPCODE_KIL] ||
-                       state->info.opcode_count[TGSI_OPCODE_KILP]);
    return state;
 }