This driver uses some sysfs helper functions that are available only for legacy
drivers. It also requires linux/mm.h.

This patch fixes compiliation when not in compat mode.

Thanks to Ingo Molnar for identifying this issue.
Acked-by: Jaime Velasco Juan <jsagarribay@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>