sys-apps/kexec-tools: respect CFLAGS for purgatory
Only when building purgatory, replace -mfunction-return=thunk and
-mindirect-branch=thunk flags with similar -mfunction-return=thunk-inline
and -mindirect-branch=thunk-inline flags, which are not incompatible
with flags added by build system.
Closes: https://bugs.gentoo.org/646536
Closes: https://bugs.gentoo.org/692930
Signed-off-by: Arfrever Frehtes Taifersar Arahesis <Arfrever@Apache.Org>
Package-Manager: Portage-2.3.99, Repoman-2.3.22
Signed-off-by: Thomas Deutschmann <whissi@gentoo.org>