Include sys/time.h for struct timespec.

--- goo/gfile.h.orig	2018-03-18 18:23:49.000000000 +0000
+++ goo/gfile.h
@@ -37,6 +37,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stddef.h>
+#include <sys/time.h>
 extern "C" {
 #if defined(_WIN32)
 #  include <sys/stat.h>

--- poppler/CMap.cc.orig	2018-03-18 18:23:49.000000000 +0000
+++ poppler/CMap.cc
@@ -33,6 +33,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
+#include <sys/time.h>
 #include "goo/gmem.h"
 #include "goo/gfile.h"
 #include "goo/GooString.h"