mesa: Clean up "unused parameter" warnings

program/ir_to_mesa.cpp:2008:1: warning: unused parameter 'ir' [-Wunused-parameter]
program/ir_to_mesa.cpp:2272:1: warning: unused parameter 'ir' [-Wunused-parameter]
program/ir_to_mesa.cpp:2278:1: warning: unused parameter 'ir' [-Wunused-parameter]

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/program/ir_to_mesa.cpp

@@ -1963,7 +1963,7 @@ ir_to_mesa_visitor::visit(ir_constant *ir)
 }
 
 void
-ir_to_mesa_visitor::visit(ir_call *ir)
+ir_to_mesa_visitor::visit(ir_call *)
 {
    assert(!"ir_to_mesa: All function calls should have been inlined by now.");
 }
@@ -2227,13 +2227,13 @@ ir_to_mesa_visitor::visit(ir_if *ir)
 }
 
 void
-ir_to_mesa_visitor::visit(ir_emit_vertex *ir)
+ir_to_mesa_visitor::visit(ir_emit_vertex *)
 {
    assert(!"Geometry shaders not supported.");
 }
 
 void
-ir_to_mesa_visitor::visit(ir_end_primitive *ir)
+ir_to_mesa_visitor::visit(ir_end_primitive *)
 {
    assert(!"Geometry shaders not supported.");
 }