broadcom/vc5: Fix pasteo that broke vertex texturing.

We weren't ever filling in the texture state record, so we'd dereference
NULL from the shader.

src/gallium/drivers/vc5/vc5_emit.c

@@ -408,7 +408,7 @@ vc5_emit_state(struct pipe_context *pctx)
                 emit_textures(vc5, &vc5->fragtex);
 
         if (vc5->dirty & VC5_DIRTY_VERTTEX)
-                emit_textures(vc5, &vc5->fragtex);
+                emit_textures(vc5, &vc5->verttex);
 
         if (vc5->dirty & VC5_DIRTY_FLAT_SHADE_FLAGS) {
                 /* XXX: Need to handle more than 24 entries. */