bfd: add missing include <time.h>

bdfio.c is defining bfd_get_current_time which is returning a time_t.
This type is defined in time.h and thus, must be included in bfd main
header to avoid undefined type when include bfd.h.

Note that most of the time, <time.h> is pulled by <sys/stat.h> already
included in bfd.h. That's why it went unnoticed.

bfd/bfd-in.h

@@ -36,6 +36,7 @@ extern "C" {
 #include "symcat.h"
 #include <stdint.h>
 #include <stdbool.h>
+#include <time.h>
 #include "diagnostics.h"
 #include <stdarg.h>
 #include <string.h>

bfd/bfd-in2.h

@@ -44,6 +44,7 @@ extern "C" {
 #include "symcat.h"
 #include <stdint.h>
 #include <stdbool.h>
+#include <time.h>
 #include "diagnostics.h"
 #include <stdarg.h>
 #include <string.h>