InputOutput: replace nullptr with boost::none in Double()

Passing nullptr as the fourth argument in Double's constructor
seems to build fine on x86, but causes build failures on many
other architectures.

Replace it with boost::none.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

diff --git a/pv/binding/inputoutput.cpp b/pv/binding/inputoutput.cpp
index 956b12b32ff4d04de89c7e26f84352b689520930..0dc0fc19dd5a8e6d38ac7bf79ebd89c9705cf92c 100644 (file)
--- a/pv/binding/inputoutput.cpp
+++ b/pv/binding/inputoutput.cpp
@@ -85,7 +85,7 @@ InputOutput::InputOutput(
                        prop = shared_ptr<Property>(new Bool(name, get, set));
                else if (def_val.is_of_type(VariantType("d")))
                        prop = shared_ptr<Property>(new Double(name, 2, "",
-                               nullptr, nullptr, get, set));
+                               none, none, get, set));
                else if (def_val.is_of_type(VariantType("i")) ||
                        def_val.is_of_type(VariantType("t")) ||
                        def_val.is_of_type(VariantType("u")))