lib:replace: Fix linking when libtirpc-devel overwrites system headers

lib:replace: Fix linking when libtirpc-devel overwrites system headers

Some systems (like SUSE currently) install the new tirpc headers by
overwritting the existing system location used by gcc. This patch will
detect if the headers in the system location belong to tirpc or not.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13341

Signed-off-by: Noel Power <noel.power@suse.com>
Reviewed-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Alexander Bokovoy <ab@samba.org>
Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org>
Autobuild-Date(master): Tue Mar 20 16:07:05 CET 2018 on sn-devel-144