ia64's ld does not implement '-z relro'. This means
'z relro --fatal-warnings' always fails on ia64.
The change drops '--fatal-warnings'.
Reported-by: Émeric Maschino
Closes: https://bugs.gentoo.org/749963
Package-Manager: Portage-3.0.8, Repoman-3.0.2
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>