greybus: kernel_ver: add list_last_entry for old kernels

Add list_last_entry macro for kernels older than 3.13.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/kernel_ver.h

@@ -235,4 +235,9 @@ static inline size_t sg_pcopy_from_buffer(struct scatterlist *sgl,
 }
 #endif
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 13, 0)
+#define list_last_entry(ptr, type, member) \
+	list_entry((ptr)->prev, type, member)
+#endif
+
 #endif	/* __GREYBUS_KERNEL_VER_H */