Explicitely included unistd.h in all source file which use ssize_t

libisofs/ecma119.c

@@ -41,6 +41,7 @@
 #include <locale.h>
 #include <langinfo.h>
 #include <stdio.h>
+#include <unistd.h>
 
 #ifdef Xorriso_standalonE
 

libisofs/fs_image.c

@@ -36,6 +36,7 @@
 #include <limits.h>
 #include <stdio.h>
 #include <ctype.h>
+#include <unistd.h>
 
 
 /* Enable this and write the correct absolute path into the include statement

libisofs/rockridge.c

@@ -15,6 +15,7 @@
 
 #include <string.h>
 #include <stdio.h>
+#include <unistd.h>
 
 #include "rockridge.h"
 #include "node.h"

libisofs/stream.c

@@ -22,6 +22,7 @@
 #include <string.h>
 #include <limits.h>
 #include <stdio.h>
+#include <unistd.h>
 
 
 #ifndef PATH_MAX