Adjust obsolete comment explaining set_stack_base().
Commit 7389aad6 removed the notion of backends started from inside a
signal handler. A stray comment still referred to them, while
explaining the need for a call to set_stack_base(). That leads to the
question of whether we still need the call
Adjust obsolete comment explaining set_stack_base().
Commit 7389aad6 removed the notion of backends started from inside a
signal handler. A stray comment still referred to them, while
explaining the need for a call to set_stack_base(). That leads to the
question of whether we still need the call
