Detect EAF flags in ipa-modref

[Jan Hubicka]

> > Bootstrapped/regtested x86_64-linux, OK?
> > (I will analyze more the t2.c failure)
> 
> I have found independent reproducer that is now in
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97775
... and with Jakub's fix the testcase works now.
Honza
> 
> Honza