Fix build on FreeBSD/i386 where time_t is int

--- configure.orig	2024-05-26 20:34:22 UTC
+++ configure
@@ -280,6 +280,19 @@ int test(void)
 }
 '
 
+check_cc_snippet time_d '
+#define _FILE_OFFSET_BITS 64
+#define _TIME_BITS 64
+#include <stdio.h>
+#include <time.h>
+#define TEST test
+int test(void)
+{
+  printf("%d", (time_t)1);
+  return 0;
+}
+' '-Wformat -Werror=format'
+
 check_cc_snippet time_ld '
 #define _FILE_OFFSET_BITS 64
 #define _TIME_BITS 64
@@ -310,6 +323,8 @@ elif enabled time_ld; then
   printf "    ^ using time_t format 'lld'\n"
 elif enabled time_ld; then
   printf "    ^ using time_t format 'ld'\n"
+elif enabled time_d; then
+  printf "    ^ using time_t format 'd'\n"
 else
   die 'Unable to determine size of "time_t"'
 fi