glsl: remove placeholder comment

This was added in 2d03f48a65 and seems like it was intended
as a TODO comment in a function stub rather than a useful
code comment.

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/compiler/glsl/ast_to_hir.cpp

@@ -7677,10 +7677,6 @@ ast_interface_block::hir(exec_list *instructions,
                                "invalid qualifier for block",
                                this->block_name);
 
-   /* The ast_interface_block has a list of ast_declarator_lists.  We
-    * need to turn those into ir_variables with an association
-    * with this uniform block.
-    */
    enum glsl_interface_packing packing;
    if (this->layout.flags.q.shared) {
       packing = GLSL_INTERFACE_PACKING_SHARED;