[C++] Raw access can be noexcept.

Author: mjpt777

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/cpp/CppGenerator.java

@@ -2287,7 +2287,7 @@ private void generateEnumProperty(
                 constValue.substring(constValue.indexOf(".") + 1));
 
             new Formatter(sb).format("\n" +
-                indent + "    SBE_NODISCARD %1$s %2$sRaw() const\n" +
+                indent + "    SBE_NODISCARD %1$s %2$sRaw() const SBE_NOEXCEPT\n" +
                 indent + "    {\n" +
                 indent + "        return static_cast<%1$s>(%3$s::Value::%4$s);\n" +
                 indent + "    }\n",