pseudo.c: add explicit <sys/stat.h> include

Signed-off-by: Alexandru Ardelean <aa@ocedo.com>
diff --git a/squashfs-tools/pseudo.c b/squashfs-tools/pseudo.c
index f446534..f9bb90a 100644
--- a/squashfs-tools/pseudo.c
+++ b/squashfs-tools/pseudo.c
@@ -32,6 +32,7 @@
 #include <stdlib.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <sys/stat.h>
 #include <ctype.h>
 
 #include "pseudo.h"