changed back some cppcheck "fixes" and updated the cppcheck suppression list

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

common/utils/T/local_tracer.c

@@ -240,8 +240,7 @@ again:
 
     if (len <= 0) goto dead;
 
-    if (buf != NULL)
-      PUT(t);
+    PUT(t);
 
     switch (t) {
       case 0:

common/utils/T/tracer/multi.c

@@ -261,7 +261,6 @@ int main(int n, char **v)
       if (fds == NULL) { perror("calloc"); exit(1); }
     }
     i = 0;
-    if (fds == NULL) { perror("null fds pointer"); exit(1); }
     fds[i].fd = l;
     fds[i].events = POLLIN;
     i++;

common/utils/T/tracer/textlog.c

@@ -195,10 +195,8 @@ int main(int n, char **v)
     handle_event(h, e);
   }
 
-  if (on_off_name != NULL)
-    free(on_off_name);
-  if (on_off_action != NULL)
-    free(on_off_action);
+  free(on_off_name);
+  free(on_off_action);
 
   return 0;
 }