libctf, binutils: initial work towards libctf gettextization

We gettextize under our package name, which we change to a more
reasonable 'libctf'.  Our internationalization support is mostly
provided by ctf-intl.h, which is a copy of opcodes/opintl.h with
the non-gettext_noop N_() expansion debracketed to avoid pedantic
compiler warnings.

The libctf error strings returned by ctf_errmsg are marked up for
internationalization.

(We also adjust binutils's Makefile a tiny bit to allow for the
fact that libctf now uses functions from libintl.)

binutils/ChangeLog
2020-08-27  Nick Alcock  <nick.alcock@oracle.com>

	* Makefile.am (readelf_LDADD): Move $(LIBINTL) after $(LIBCTF_NOBFD).
	* Makefile.in: Regenerated.

libctf/ChangeLog
2020-08-27  Nick Alcock  <nick.alcock@oracle.com>

	* configure.ac: Adjust package name to simply 'libctf': arbitrarily
	declare this to be version 1.2.0.
	* Makefile.am (AM_CPPFLAGS): Add @INCINTL@.
	* Makefile.in: Regenerated.
	* configure: Regenerated.
	* ctf-intl.h: New file, lightly modified from opcodes/opintl.h.
	* ctf-impl.h: Include it.
	* ctf-error.r (_ctf_errlist_t): Mark strings as noop-translatable.
	(ctf_errmsg): Actually translate them.

libctf/ctf-impl.h

@@ -36,6 +36,7 @@
 #include <elf.h>
 #include <bfd.h>
 #include "hashtab.h"
+#include "ctf-intl.h"
 
 #ifdef	__cplusplus
 extern "C"