sdbusplus: remove deprecated variant_ns

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ib20d8676d474bcb020a5ffababd77d901360d192
diff --git a/policy_find.cpp b/policy_find.cpp
index 51576eb..191240e 100644
--- a/policy_find.cpp
+++ b/policy_find.cpp
@@ -44,7 +44,7 @@
 
     if (prop != properties.end())
     {
-        return sdbusplus::message::variant_ns::get<T>(prop->second);
+        return std::get<T>(prop->second);
     }
 
     return {};