maint: remove -Wmissing-field-initializers workarounds

* configure.ac: Rather than disabling -Wmissing-field-initializers,
use the fact that gnulib now disables it automatically when required
(on versions of GCC older than 4.7).
* src/system.h: Remove the no longer needed DECLARE_ZEROED_AGGREGATE.
* src/ls.c: Likewise.
* src/pathchk.c: Likewise.
* src/shred.c: Likewise.
* src/stty.c: Likewise.
* src/wc.c: Likewise.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/ls.c b/src/ls.c
index a7ea8c2cb..4262923ce 100644
--- a/src/ls.c
+++ b/src/ls.c
@@ -3891,7 +3891,7 @@ quote_name (FILE *out, const char *name, struct quoting_options const *options,
                      reach its end, replacing each non-printable multibyte
                      character with a single question mark.  */
                   {
-                    DECLARE_ZEROED_AGGREGATE (mbstate_t, mbstate);
+                    mbstate_t mbstate = { 0, };
                     do
                       {
                         wchar_t wc;