[naga glsl-in] Fix double overload for dot/reflect/distance/ldexp.

The first argument of the `dot`, `reflect`, `distance`, and `ldexp`
GLSL builtin functions may be either a float or a double, and thus the
argument type registered by `inject_common_builtin` must depend on the
`float_width` argument; it cannot simply be `Scalar::F32`.

Introduced by gfx-rs#4673.

naga/src/front/glsl/builtins.rs

@@ -1257,7 +1257,7 @@ fn inject_common_builtin(
 
  declaration
  .overloads
- .push(module.add_builtin(vec![ty(Scalar::F32), ty(second_scalar)], fun))
+ .push(module.add_builtin(vec![ty(float_scalar), ty(second_scalar)], fun))
  }
  }
  "transpose" => {