bmcweb: Fix a bunch of warnings

bmcweb classically has not taken a strong opinion on warnings.  With
this commit, that policy is changing, and bmcweb will invoke the best
warnings we are able to enable, and turn on -Werror for all builds.

This is intended to reduce the likelihood of hard-to-debug situations
that the compiler coulve caught early on.

Change-Id: I57474410821e82666b3a108cfd0db7d070e8900a
Signed-off-by: Ed Tanous <ed@tanous.net>
diff --git a/include/openbmc_dbus_rest.hpp b/include/openbmc_dbus_rest.hpp
index ab35bb2..e596920 100644
--- a/include/openbmc_dbus_rest.hpp
+++ b/include/openbmc_dbus_rest.hpp
@@ -570,8 +570,9 @@
             {
                 return -1;
             }
-            r = sd_bus_message_append_basic(m, argCode[0],
-                                            (void *)stringValue->c_str());
+            r = sd_bus_message_append_basic(
+                m, argCode[0],
+                reinterpret_cast<const void *>(stringValue->c_str()));
             if (r < 0)
             {
                 return r;
@@ -737,13 +738,13 @@
             }
 
             nlohmann::json::const_iterator it = j->begin();
-            for (const std::string &argCode : dbusArgSplit(arg_type))
+            for (const std::string &argCode2 : dbusArgSplit(arg_type))
             {
                 if (it == j->end())
                 {
                     return -1;
                 }
-                r = convertJsonToDbus(m, argCode, *it);
+                r = convertJsonToDbus(m, argCode2, *it);
                 if (r < 0)
                 {
                     return r;