add errno.h to fix compile errors on other devices

Change-Id: I84196fb1358264b216b8505b990ae5a0406aa957
diff --git a/fixPermissions.hpp b/fixPermissions.hpp
index aa6f609..6439dac 100644
--- a/fixPermissions.hpp
+++ b/fixPermissions.hpp
@@ -8,6 +8,7 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <dirent.h>
+#include <errno.h>
 #include "gui/rapidxml.hpp"
 #include "twrp-functions.hpp"