src: optionally include xlocale.h header

On macOS some definitions are in xlocale.h, instead of in
locale.h. GNULIB hides this difference by making the latter
include the former.
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

configure.ac

@@ -399,6 +399,7 @@ AC_CHECK_HEADERS([\
   sys/syscall.h \
   sys/sysctl.h \
   sys/ucred.h \
+  xlocale.h \
   ])
 dnl Check whether endian provides handy macros.
 AC_CHECK_DECLS([htole64], [], [], [[#include <endian.h>]])

src/util/virgettext.c

@@ -21,6 +21,9 @@
 #include <config.h>
 
 #include <locale.h>
+#ifdef HAVE_XLOCALE_H
+# include <xlocale.h>
+#endif
 
 #include "configmake.h"
 #include "internal.h"

src/util/virstring.c

@@ -20,6 +20,9 @@
 
 #include <glib/gprintf.h>
 #include <locale.h>
+#ifdef HAVE_XLOCALE_H
+# include <xlocale.h>
+#endif
 
 #include "virstring.h"
 #include "virthread.h"

tests/vshtabletest.c

@@ -19,6 +19,9 @@
 #include <config.h>
 
 #include <locale.h>
+#ifdef HAVE_XLOCALE_H
+# include <xlocale.h>
+#endif
 #include <wchar.h>
 #include <wctype.h>