Cppcheck does not know how FormatMessage() works. Ignore the message.

Add LocalFree() to prevent leak.

Author: BsAtHome

src/emc/usr_intf/sockets.c

@@ -276,9 +276,12 @@ char* sockGetError(void)
 
     /* append the message text after the error code and ensure a terminating
        character ends the string */
+  // The 'tmp' buffer is allocated by FormatMessage().
+  // cppcheck-suppress nullPointer
   strncpy(retString + strlen(retString), tmp, 
           sizeof(retString) - strlen(retString) - 1);
   retString[sizeof(retString) - 1] = '\0';
+  LocalFree(tmp);
 
   return retString;
 #endif