sparc: remove unused header file nfs_fs.h

Remove unused header file linux/nfs_fs.h

Signed-off-by: Anupam Aggarwal <anupam.al@samsung.com>
Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>