Remove redundant check for tb != NULL to shut up Coverity . It has been set to...

Remove redundant check for tb != NULL to shut up Coverity . It has been set to Py_None a couple of lines earlier.
CID 1291697 (#1 of 1): Dereference before null check (REVERSE_INULL)
check_after_deref: Null-checking tb suggests that it may be null, but it has already been dereferenced on all paths leading to the check.

Python/pylifecycle.c

@@ -1283,7 +1283,7 @@ _Py_PrintFatalError(int fd)
         goto display_stack;
     }
 
-    has_tb = (tb != NULL && tb != Py_None);
+    has_tb = (tb != Py_None);
     PyErr_Display(exception, v, tb);
     Py_XDECREF(exception);
     Py_XDECREF(v);