std::variant: Fixup apply_visitor calls

These should be std::visit compatible instead of the custom mapbox
apply_visitor.

Change-Id: I32098c02bda5a3699abace919426a6e4b9c8ae9c
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/dbus/dbuspassive.cpp b/dbus/dbuspassive.cpp
index 3a6d6d4..4bfac57 100644
--- a/dbus/dbuspassive.cpp
+++ b/dbus/dbuspassive.cpp
@@ -124,7 +124,7 @@
         auto valPropMap = msgData.find("Value");
         if (valPropMap != msgData.end())
         {
-            double value = sdbusplus::message::variant_ns::apply_visitor(
+            double value = sdbusplus::message::variant_ns::visit(
                 VariantToDoubleVisitor(), valPropMap->second);
 
             value *= std::pow(10, owner->getScale());