glsl: make use of glsl_type::is_double()

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Edward O'Callaghan <funfunctor@folklore1984.net>

src/compiler/glsl/ir_equals.cpp

@@ -58,7 +58,7 @@ ir_constant::equals(const ir_instruction *ir, enum ir_node_type) const
       return false;
 
    for (unsigned i = 0; i < type->components(); i++) {
-      if (type->base_type == GLSL_TYPE_DOUBLE) {
+      if (type->is_double()) {
          if (value.d[i] != other->value.d[i])
             return false;
       } else {