Enable init checker

clang-tidy added cppcoreguidelines-init-variables as a check, which is
something we already enforce to some extent, but getting CI to enforce
it will help reviews move faster.

Tested: Code compiles.  Noop changes.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I7e10950de617b1d3262265572b1703f2e60b69d0
diff --git a/redfish-core/lib/ethernet.hpp b/redfish-core/lib/ethernet.hpp
index 8735178..ee8d2cd 100644
--- a/redfish-core/lib/ethernet.hpp
+++ b/redfish-core/lib/ethernet.hpp
@@ -635,9 +635,9 @@
         *bits = 0;
     }
 
-    char* endPtr;
+    char* endPtr = nullptr;
     long previousValue = 255;
-    bool firstZeroInByteHit;
+    bool firstZeroInByteHit = false;
     for (const std::string& byte : bytesInMask)
     {
         if (byte.empty())
@@ -1581,8 +1581,8 @@
                 return;
             }
 
-            const std::string* addr;
-            uint8_t prefix;
+            const std::string* addr = nullptr;
+            uint8_t prefix = 0;
 
             // Find the address and prefixLength values. Any values that are
             // not explicitly provided are assumed to be unmodified from the