replace: Add check for variable program_invocation_short_name

replace: Add check for variable program_invocation_short_name

It appears that wafsamba's configure() defines _GNU_SOURCE
unconditionally, so checking _GNU_SOURCE isn't enough to know if this
variable is available.

For example, it isn't available on AIX with the xlc compiler:

  [ 6/10] Compiling lib/replace/replace.c
  ...
  "../../lib/replace/replace.c", line 991.16: 1506-045 (S) Undeclared identifier program_invocation_short_name.

Instead, add a configure check for program_invocation_short_name and
use it.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Andreas Schneider <asn@samba.org>
Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org>
Autobuild-Date(master): Tue Nov 13 11:11:11 CET 2018 on sn-devel-144