nfs-utils: fix struct file_handle related build failures

This patch fixes
http://autobuild.buildroot.net/results/948/948f81d7ed2c080a675ee9fec754f6fda1fd905f/

The patches has been sent upstream:
http://article.gmane.org/gmane.linux.nfs/76139



Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
[Thomas: slightly tweak commit title.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>