move variant to std namespace

sdbusplus::message::variant_ns has been std for a while now. This moves
ipmid away from sdbusplus::message::variant_ns to directly use
std::variant.

Tested-by: built, compiles, and runs the same as before.

Change-Id: I8caa945f31c926c2721319f001b9d7f83fd3f1b7
Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com>
diff --git a/libipmid/utils.cpp b/libipmid/utils.cpp
index 3ff79ed..b8ba9a7 100644
--- a/libipmid/utils.cpp
+++ b/libipmid/utils.cpp
@@ -15,7 +15,6 @@
 
 using namespace phosphor::logging;
 using namespace sdbusplus::xyz::openbmc_project::Common::Error;
-namespace variant_ns = sdbusplus::message::variant_ns;
 
 namespace network
 {
@@ -118,7 +117,7 @@
         objectInfo = std::make_pair(object.first, object.second.begin()->first);
 
         // if LinkLocalIP found look for Non-LinkLocalIP
-        if (ipmi::network::isLinkLocalIP(variant_ns::get<std::string>(variant)))
+        if (ipmi::network::isLinkLocalIP(std::get<std::string>(variant)))
         {
             continue;
         }