Enable LTO

Related: RHEL-30627

By default, Fedora's libbpf has LTO turned off (probably for historical
reasons). Since RHEL has more strict hardening checks, we need to enable
it.

Signed-off-by: Viktor Malik <vmalik@redhat.com>

libbpf.spec

@@ -9,7 +9,7 @@
 
 Name:           libbpf
 Version:        1.4.0
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:        Libbpf library
 
 License:        LGPL-2.1-only OR BSD-2-Clause
@@ -45,8 +45,6 @@ Requires: %{name}-devel = 2:%{version}-%{release}
 The %{name}-static package contains static library for
 developing applications that use %{name}
 
-%define _lto_cflags %{nil}
-
 %global libbpf_make \
     make prefix=%{_prefix} DESTDIR=%{buildroot} OBJDIR=%{_builddir} CFLAGS="%{build_cflags} -fPIC" LDFLAGS="%{build_ldflags} -Wl,--no-as-needed" LIBDIR=/%{_libdir} NO_PKG_CONFIG=1